Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix...

88
Quantum chemical molecular modelling Dr. hab. Artur Michalak Department of Theoretical Chemistry Faculty of Chemistry Jagiellonian University Kraków, Poland http://www.chemia.uj.edu.pl/~michalak/mmod/ http://www.chemia.uj.edu.pl/~michalak/mmod2008/ In Polish: http://www.chemia.uj.edu.pl/~michalak/mmod2007/ Ck08 Lecture 2

Transcript of Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix...

Page 1: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Quantum chemical molecular modelling

Dr. hab. Artur MichalakDepartment of Theoretical Chemistry

Faculty of ChemistryJagiellonian University

Kraków, Poland

http://www.chemia.uj.edu.pl/~michalak/mmod/http://www.chemia.uj.edu.pl/~michalak/mmod2008/

In Polish: http://www.chemia.uj.edu.pl/~michalak/mmod2007/

Ck08

Lecture 2

Page 2: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

• Basic ideas and methods of quantum chemistry:Wave-function; Electron density; Schrodinger equation; Density Functional theory; Born-Oppenheimer approximation; Variational principles in wave-function mechanics and DFT; One-electron approximation; HF method; Electron correlation; KS method; Wave-function-based electron correlation methods;

• Input data for QM calculations, GAMESS program:Molecular geometry, Z-Matrix, Basis sets in ab initio

calculations; input, output;

• Geometry of molecular systems: Geometry optimization; Constrained optimization; Conformational analysis; Global minimum problem

• Electronic structure of molecular systems: Molecular orbitals (KS orbitals); Chemical bond; Deformation density; Localized orbitals; Population analysis; Bond-orders

•Molecular vibrations, Thermodynamics; Chemical Reactivity:Vibrational analysis; Thermodynamic properties; Modeling chemical reactions; Trantition state optimization and validation; Intrinsic Reaction Coordinate; Chemical reactivity indices; Molecular Electrostatic Potential; Fukui Functions; Single- and Two-Reactant Reactivity Indices

• Other Topics:Modelling of complex chemical processes – examples from catalysis; Molecular spectroscopy from ab initio

calculations; Advanced methods for electron correlation;Molecular dynamics; Modelling of large systems –hybrid approaches (QM/MM); Solvation models

Page 3: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

SoftwareSoftware

• GAUSSIAN• GAMESS• NWCHEM• TURBOMOLE• DMol• DeMon• DGauss• DeFT• ADF

• and many others

• GAUSSIAN• GAMESS• NWCHEM• TURBOMOLE• DMol• DeMon• DGauss• DeFT• ADF

• and many others

Page 4: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

SoftwareSoftware

• GAUSSIAN• GAMESS• NWCHEM• TURBOMOLE• DMol• DeMon• DGauss• DeFT• ADF

• and many others

• GAUSSIAN• GAMESS• NWCHEM• TURBOMOLE• DMol• DeMon• DGauss• DeFT• ADF

• and many others

Page 5: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Static calculations(BO approximation)Static calculations

(BO approximation)

• Wave-function / electron density optimization (for assumed molecular geometry) ���� the electronic energy

• Geometry optimization

• Vibrational frequencies

• Molecular properties based on the wave-function / electron density

• Wave-function / electron density optimization (for assumed molecular geometry) ���� the electronic energy

• Geometry optimization

• Vibrational frequencies

• Molecular properties based on the wave-function / electron density

Page 6: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Input dataInput dataatoms zmatrix

1 H 0 0 0 0.0 0.0 0.0

2 O 1 2 0 0.99 0.0 0.0

3 H 2 1 3 0.99 105.0 0.0

end

basis

type sz

core none

end

xc

lda scf vwn

end

symmetry tol=0.001

geometry

optim all internal

iterations 30

step rad=0.15 angle=10.0

hessupd bfgs

converge e=1.0e-3 grad=1.0e-2 rad=1.0e-2 angle=0.5

end

scf

iterations 50

converge 1.0e-6 1.0e-3

mixing 0.2

lshift 0.0

diis n=10 ok=0.5 cyc=5 cx=5.0 cxx=10.0

end

integration 3.0 4.0 4.0

units

length angstrom

$CONTRL SCFTYP=RHF RUNTYP=OPTIMIZE

COORD=ZMT ICHARG=0 MULT=1 $END

$SYSTEM TIMLIM=90 MEMORY=1000000 $END

$STATPT OPTTOL=1.0E-3 NSTEP=100 $END

$BASIS GBASIS=STO NGAUSS=3 $END

$SCF DIRSCF=.TRUE. $END

$GUESS GUESS=HUCKEL $END

$DATA

h2o

C1

H

O 1 1.0

H 2 1.0 1 105.0

$END

$CONTRL SCFTYP=RHF RUNTYP=OPTIMIZE

COORD=ZMT ICHARG=0 MULT=1 $END

$SYSTEM TIMLIM=90 MEMORY=1000000 $END

$STATPT OPTTOL=1.0E-3 NSTEP=100 $END

$BASIS GBASIS=STO NGAUSS=3 $END

$SCF DIRSCF=.TRUE. $END

$GUESS GUESS=HUCKEL $END

$DATA

h2o

C1

H

O 1 1.0

H 2 1.0 1 105.0

$END

GAMESS

ADF1. Text file:

keywords, values of parametrers, etc.

Page 7: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Input dataInput data

Interfejs graficznyprogramuADF 2005

2. GUI (graphical user interface)

Page 8: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Data set for quantum chemical calculations

Data set for quantum chemical calculations

• Unique definition of the molecule and its electronic state

• Choice of methodology

• Basis set specification

• Choice of computational details: alghoritms, parameters characteristic for a given method, etc. (that influence accuracy of calculations); choice of properties to be calculated

• Unique definition of the molecule and its electronic state

• Choice of methodology

• Basis set specification

• Choice of computational details: alghoritms, parameters characteristic for a given method, etc. (that influence accuracy of calculations); choice of properties to be calculated

Page 9: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Default charge - 0Default charge - 0Nuclei: H, C, N

Charge 0

(14 electrons)

MoleculeMolecule

• Number and types of nuclei forming the molecule;• Number and types of nuclei forming the molecule;

• Number of electrons (charge of molecule)• Number of electrons (charge of molecule)

HCN CNH TS

Page 10: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

• Positions of nuclei• Positions of nuclei

• Electronic state (multiplicity, numbers of αααα and ββββ electrons)• Electronic state (multiplicity, numbers of αααα and ββββ electrons)

Singlet: nαααα-nββββ = 0 = 0 = 0 = 0 (default)

Doublet: nαααα-nββββ = 1= 1= 1= 1

Triplet: nαααα-nββββ = 2, = 2, = 2, = 2, etc.

Singlet: nαααα-nββββ = 0 = 0 = 0 = 0 (default)

Doublet: nαααα-nββββ = 1= 1= 1= 1

Triplet: nαααα-nββββ = 2, = 2, = 2, = 2, etc.

MoleculeMolecule

• Number and types of nuclei forming the molecule;• Number and types of nuclei forming the molecule;

• Number of electrons (charge of molecule)• Number of electrons (charge of molecule)

Page 11: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Units??? a.u. (bohr)Å

Molecular geometry -cartesian coordinatesMolecular geometry -cartesian coordinates

z

cartesian angstrom

H 0.00 0.00 0.00

C 0.00 0.00 1.00

N 0.00 0.00 2.20

end

Page 12: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Molecular geometry -cartesian coordinatesMolecular geometry -cartesian coordinates

Page 13: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Bond lengths, bond angles, torsional angles

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 14: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

N atoms - 3N cartesian coords

3N-6 internal coorrds

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Choice of atom order

Choice of coordinates (reference atoms)

Choice of atom order

Choice of coordinates (reference atoms)

Page 15: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

H

C 1 1.00

N 2 1.20 1 180.0

end

1 2 3

zmatrix angstrom

H

C 1 1.00

N 1 2.20 2 0.0

end

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 16: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl

H

H

H

H

H

end

12

4

3 5

67

8

9

chloropropylene

(3-chloro-propene)

For the 4th atom and following we have to specify:Distance and 2 angles,

i.e. bond angleandtorsion

For the 4th atom and following we have to specify:Distance and 2 angles,

i.e. bond angleandtorsion

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 17: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

In general: for atom n , defined with respect to atoms i j k,

we specify distance rni, , angle ααααnij and ββββnijk

Torsion ββββnijk is defined as rotation of the n-i bond around thei-j bond, with respect to the j-k bond.

ni

j

k

i, j

k

n

ββββnijk = 90o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 18: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

ni

j

k

i, j

k

nββββnijk = 120o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

In general: for atom n , defined with respect to atoms i j k,

we specify distance rni, , angle ααααnij and ββββnijk

Torsion ββββnijk is defined as rotation of the n-i bond around thei-j bond, with respect to the j-k bond.

Page 19: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

ni

j

k

i, j

k

n

ββββnijk = 180o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

In general: for atom n , defined with respect to atoms i j k,

we specify distance rni, , angle ααααnij and ββββnijk

Torsion ββββnijk is defined as rotation of the n-i bond around thei-j bond, with respect to the j-k bond.

Page 20: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H

H

H

H

H

end

12

4

3 5

67

8

9

chloropropylene

(3-chloropropene)

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 21: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3

H

H

H

H

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 22: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H

H

H

H

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 23: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3

H

H

H

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 24: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3 180.0

H

H

H

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 25: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3 180.0

H 2 1.09 1 120.0 6

H

H

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 26: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3 180.0

H 2 1.09 1 120.0 6 0.0

H

H

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 27: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3 180.0

H 2 1.09 1 120.0 6 0.0

H 3 1.09 2 109.5 1

H 3 1.09 2 109.5 1

end

12

4

3 5

67

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 28: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3 180.0

H 2 1.09 1 120.0 6 0.0

H 3 1.09 2 109.5 1

H 3 1.09 2 109.5 1

end

12

4

3 5

67

8

9

3,21

4

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 29: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

zmatrix angstrom

C

C 1 1.38

C 2 1.50 1 120.0

Cl 3 1.83 2 109.5 1 0.0

H 1 1.09 2 120.0 3 0.0

H 1 1.09 2 120.0 3 180.0

H 2 1.09 1 120.0 6 0.0

H 3 1.09 2 109.5 1 120.0

H 3 1.09 2 109.5 1 -120.0

end

12

4

3 5

67

8

9

3,21

4

8

9

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

chloropropylene

(3-chloropropene)

Page 30: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

j.k1

i

2

3

Atoms 1, 2, 3 linked toatom k - with sp3 hybridization

Angles: 1-k-j-i 0o

2-k-j-i 120o

3-k-j-i 240o (–120o)

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 31: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

j.k1

i

2

3

Atomy 1, 2, 3 połączone zatomem k - o hybrydyzacji sp3

Angles: 1-k-j-i αααα2-k-j-i α + α + α + α + 1203-k-j-i α α α α – 120

α

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Atoms 1, 2, 3 linked toatom k - with sp3 hybridization

Page 32: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

j.k 1i2

Angles: 1-k-j-i 0o

2-k-j-i 180o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Atoms 1, 2, 3 linked toatom k - with sp2 hybridization

Page 33: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

j.k 1i2

j.k1

i

2

3

αααα

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Angles: 1-k-j-i αααα2-k-j-i α + α + α + α + 1203-k-j-i α α α α – 120

Atoms 1, 2, 3 linked toatom k - with sp3 hybridization

Angles: 1-k-j-i 0o

2-k-j-i 180o

Atoms 1, 2, 3 linked toatom k - with sp2 hybridization

Page 34: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Methyl acrylate, CH2=CH-COOCH3

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 35: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0OOCHHHHHH

123456789

101112

Page 36: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0OCHHHHHH

123456789

101112

Page 37: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0CHHHHHH

123456789

101112

Page 38: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0C 5 1.35 3 109.5 2 180.0HHHHHH

123456789

101112

Page 39: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0C 5 1.35 3 109.5 2 180.0H 1 1.10 2 120.0 3 0.0HHHHH

123456789

101112

Page 40: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0C 5 1.35 3 109.5 2 180.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0HHHH

123456789

101112

Page 41: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0C 5 1.35 3 109.5 2 180.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 120.0 7 180.0HHH

123456789

101112

Page 42: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0C 5 1.35 3 109.5 2 180.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 120.0 7 180.0H 6 1.10 5 109.5 3 0.0HH

123456789

101112

Page 43: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

67

89

10

1112

zmatrix angstromCC 1 1.33C 2 1.45 1 120.0O 3 1.25 2 120.0 1 0.0O 3 1.35 2 120.0 1 180.0C 5 1.35 3 109.5 2 180.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 120.0 7 180.0H 6 1.10 5 109.5 3 0.0H 6 1.10 5 109.5 3 120.0 H 6 1.10 5 109.5 3 -120.0

123456789

101112

Page 44: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Linear molecules(or with linear arrangement of a few atoms)

acetylene

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 45: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

acetylene

HC 1 1.10C 2 1.25 1 180.0

H 3 1.10 2 180.0 1 ?????1

2

3

4

Torsion ill-defined!!!!

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Linear molecules(or with linear arrangement of a few atoms)

Page 46: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

„dangerous” value of the bond angle: 180o

– torsion ill-defined

ni

j

k

i, j

k

nββββnijk = 120o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 47: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

ni

j

k

i, j

k

nββββnijk = 120o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined

Page 48: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

ni

j

k

i, j

k

nββββnijk = 120o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined

Page 49: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

i, j

k

nββββnijk = 120o

ni

j

k

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined

Page 50: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

ni

j

k

i, j

k

nββββnijk = ???????

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined

Page 51: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

i, j

k

nββββnijk = -60o !!!!n

ij

k

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined

Page 52: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

ni

j

k

i, j

k

nββββnijk = 120o

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined

Page 53: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

acetylene

5

1

2

6

3

4

CC 1 1.10XX 2 1.00 1 90.0XX 1 1.00 2 90.0 3 0.0

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined‘ghost atoms’ can be introduced, i.e. auxiliary reference points

Page 54: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

acetylen

5

1

2

6

3

4

CC 1 1.10XX 2 1.00 1 90.0XX 1 1.00 2 90.0 3 0.0H 1 1.10 4 90.0 3 180.0H 2 1.10 3 90.0 4 180.0

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

„dangerous” value of the bond angle: 180o

– torsion ill-defined‘ghost atoms’ can be introduced, i.e. auxiliary reference points

Page 55: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Acrylonitril CH2=CH-CN

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 56: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Acrylonitril CH2=CH-CN

123

4

5

6

7

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 57: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Ethylene

12

3

45

6zmatrix angstromCC 1 1.33H 2 1.10 1 120.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 109.5 4 0.0

123456

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 58: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Acrylonitril CH2=CH-CN

123

4

5

6

7zmatrix angstromCC 1 1.33C 2 1.40 1 120.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 109.5 4 0.0

123456

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 59: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

6

7zmatrix angstromCC 1 1.33C 2 1.40 1 120.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 109.5 4 0.0N 3 1.15 2 180.0 1 ?????

1234567

ill-defined

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Acrylonitril CH2=CH-CN

Page 60: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

6

8zmatrix angstromCC 1 1.33C 2 1.40 1 120.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 109.5 4 0.0XX 3 1.00 2 90.0 1 180.0N 3 1.15 7 90.0 2 180.0

12345678

7

XX

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Acrylonitril CH2=CH-CN

Page 61: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

6

7zmatrix angstromCC 1 1.33C 2 1.40 1 120.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 109.5 4 0.0N ??????????????????????????

1234567

Another trick(No GHOSTS)

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Acrylonitril CH2=CH-CN

Page 62: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

123

4

5

6

7zmatrix angstromCC 1 1.33C 2 1.40 1 120.0H 1 1.10 2 120.0 3 0.0H 1 1.10 2 120.0 3 180.0H 2 1.10 1 109.5 4 0.0N 2 2.55 1 109.5 4 180.0

1234567

Change of reference atoms

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Acrylonitril CH2=CH-CNAnother trick(No GHOSTS)

Page 63: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Ring systems

1

2

3

4

5

6

Z-matrix comprises distances2-1, 3-2, 4-3, 5-4, 6-5,while the distance 1-6 is not included

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 64: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

1

2

3

4

5

6

Increase in bond-angles may result in ring opening (increase in the distance1-6)

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Ring systems

Z-matrix comprises distances2-1, 3-2, 4-3, 5-4, 6-5,while the distance 1-6 is not included

Page 65: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Ring systems

12

3

4

5

6

Ghost atom in the centre of the ring and defining all the real atoms with respect to its position2-13-1-24-1-3-25-1-4-36-1-5-47-1-6-5

7

identicaldistances and angles

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 66: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Exercise 0.• Ethane, C2H6 , eclipsed and staggered

conformation• Butane, 1-butene, butadiene• Aniline, C6H5NH2

Molecular geometry -internal coordinates (Z-matrix)

Molecular geometry -internal coordinates (Z-matrix)

Page 67: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Input data – the moleculeInput data – the molecule

• Positions of nuclei• Positions of nuclei

• Electronic state (multiplicity, numbers of αααα and ββββ electrons)• Electronic state (multiplicity, numbers of αααα and ββββ electrons)

Singlet: nαααα-nββββ = 0 = 0 = 0 = 0 (default)

Doublet: nαααα-nββββ = 1= 1= 1= 1

Triplet: nαααα-nββββ = 2, = 2, = 2, = 2, etc.

Singlet: nαααα-nββββ = 0 = 0 = 0 = 0 (default)

Doublet: nαααα-nββββ = 1= 1= 1= 1

Triplet: nαααα-nββββ = 2, = 2, = 2, = 2, etc.

• Number and types of nuclei forming the molecule;• Number and types of nuclei forming the molecule;

• Number of electrons (charge of molecule)• Number of electrons (charge of molecule)

Page 68: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Basis set choiceBasis set choice

Page 69: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Computational ab initio methodsComputational ab initio methods

Hartree-Fock-Roothana method

Linear combination approach (LCAO)

One-electron orbitals expressed as a linear combination of

the basis functions

)(...)()(

)1(...)1()1(

!

1

21

21

NNN

N

N

N

ϕϕϕ

ϕϕϕ

MMMM

MMMM=Ψ

∑=

=m

j

jiji c1

)1()1( χϕ

Basis functions

Page 70: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Computational ab initio methodsComputational ab initio methods

DFT approach: KS method

Linear combination approach (LCAO)

One-electron orbitals expressed as a linear combination of

the basis functions;

Electron density as sum of squares of orbitals

∑=

=m

j

jiji rcr1

)()( χϕ

2

1

)()( ∑=

=m

i

i rr ϕρBasis functions

Page 71: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Basis setsBasis sets

LCAO approach:Linear Combination of Atomic Orbitals

The basis set used in the calculations includesfunctions representing atomic orbitals for each atom

Page 72: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Minimal basis (single-zeta)one radial function for each occupied shell

eg. for O atom:1 radial function for 1s orbital1 radial function for 2s orbital1 radial function for 2p orbital

means – three 2p functions: 2px,2py,2pz

Basis setsBasis sets

Page 73: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Minimal basis (single-zeta, SZ)one radial function for each occupied shell

eg. for O atom:1 radial function for 1s orbital1 radial function for 2s orbital1 radial function for 2p orbital

Total number: 5 basis functionsφφφφ1s , φφφφ2s, φφφφ2px, φφφφ2py, φφφφ2pz

Basis setsBasis sets

Page 74: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Double-zeta basis sets (DZ)two radial functions for each occupied shell

eg. for O atom:2 radial functions for 1s orbital2 radial functions for 2s orbital2 radial functions for 2p orbital

Total number: 10 basis functionsφφφφ1s , φφφφ2s, φφφφ2px, φφφφ2py, φφφφ2pz, φφφφ’1s , φφφφ’2s, φφφφ’2px, φφφφ’2py, φφφφ’2pz

Basis setsBasis sets

Page 75: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Double-zeta valence basis sets (DZV)two radial functions for each occupied valence shell

eg. for O atom:1 radial function for 1s orbital (core orbital)2 radial functions for 2s orbital (valence shell)2 radial functions for 2p orbital (valence shell)

Total number: 9 basis functionsφφφφ1s , φφφφ2s, φφφφ2px, φφφφ2py, φφφφ2pz, , φφφφ’2s, φφφφ’2px, φφφφ’2py, φφφφ’2pz

Basis setsBasis sets

Page 76: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Triple-zeta basis sets (TZ)three radial functions for each occupied shell

eg. for O atom:3 radial functions for 1s orbital3 radial functions for 2s orbital3 radial functions for 2p orbital

Total number: 15 basis functionsφφφφ1s , φφφφ2s, φφφφ2px, φφφφ2py, φφφφ2pz, φφφφ’1s , φφφφ’2s, φφφφ’2px, φφφφ’2py, φφφφ’2pzφφφφ”1s , φφφφ”2s, φφφφ”2px, φφφφ”2py, φφφφ”2pz

Basis setsBasis sets

Page 77: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Triple-zeta valence basis sets (TZV)three radial functions for each occupied valence shell

eg. for O atom:1 radial function for 1s orbital (core orbital)3 radial functions for 2s orbital (valence shell)3 radial functions for 2p orbital (valence shell)

Total number: 13 basis functionsφφφφ1s , φφφφ2s, φφφφ2px, φφφφ2py, φφφφ2pz, , φφφφ’2s, φφφφ’2px, φφφφ’2py, φφφφ’2pz, φφφφ”2s, φφφφ”2px, φφφφ”2py, φφφφ”2pz

Basis setsBasis sets

Page 78: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Polarization functionsAdditional basis functions corresponding to the higher

l-number (unoccupied for given atom)

eg. for O atom:Occupied orbitals: s-type, p-typePolarization functions : d-type

Basis setsBasis sets

Page 79: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Polarization functionsadded to DZ,DZV,TZ, TZV, QZ, QZV,… sets

Gives

DZP, DZVP, TZP, TZVP, QZP, QZVP, etc.

Basis setsBasis sets

Page 80: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Double-zeta polarized basis sets (DZP)two radial functions for each occupied shell

+ polarization functions

eg. for O atom:2 radial functions for 1s orbital2 radial functions for 2s orbital2 radial functions for 2p orbital1 radial d function

Total number: 15 basis functions (or 16)φφφφ1s , φφφφ2s, φφφφ2px, φφφφ2py, φφφφ2pz, φφφφ’1s , φφφφ’2s, φφφφ’2px, φφφφ’2py, φφφφ’2pzφφφφdxy , φφφφdxz, φφφφdyz, φφφφx2-y2, φφφφz2

or φφφφdxy , φφφφdxz, φφφφdyz, φφφφx2, φφφφdy2, φφφφz2

Basis setsBasis sets

Page 81: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Diffuse functions – additional functions with small exponent

used eg. for anions

Basis setsBasis sets

Page 82: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

Hydrogen atom orbitals –Slater-type functions

Problems with 3- and 4-center integrals

)exp( rα−

Basis setsBasis sets

Page 83: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

)exp( 2rα−

Gaussian functions

Analytical expressions for all sorts of integrals

Basis setsBasis sets

Hydrogen atom orbitals –Slater-type functions

Problems with 3- and 4-center integrals

)exp( rα−

Page 84: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

R

STOGTO

Basis setsBasis sets

Page 85: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

R

STO1 GTO

Slater-type function may be approximated

by a combination of gaussian-type functions

2 GTO

Basis setsBasis sets

Page 86: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

R

STO1 GTO

2 GTO

3 GTO5 GTO

Funkcje

STO-2G

STO-3G

STO-4G

STO-5G

itd.

STO-nG functions are minimal basis sets (SZ)

Basis setsBasis sets

Slater-type function may be approximated

by a combination of gaussian-type functions

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functions

3-21G

6-31G

6-311G

etc.

split-valence basis set

corresponding to. DZV, TZV, etc.

With polarization functions

6-311G*

6-311G**

With diffuse functions:

6-311G+

6-311G++

Basis setsBasis sets

Page 88: Quantum chemical molecular modellingmichalak/mmod2008/L2.pdf · Input dataInput data atoms zmatrix 1 H 0 0 0 0.0 0.0 0.0 2 O 1 2 0 0.99 0.0 0.0 3 H 2 1 3 0.99 105.0 0.0 end basis

• Basic ideas and methods of quantum chemistry:Wave-function; Electron density; Schrodinger equation; Density Functional theory; Born-Oppenheimer approximation; Variational principles in wave-function mechanics and DFT; One-electron approximation; HF method; Electron correlation; KS method; Wave-function-based electron correlation methods;

• Input data for QM calculations, GAMESS program:Molecular geometry, Z-Matrix, Basis sets in ab initio

calculations; input, output;

• Geometry of molecular systems: Geometry optimization; Constrained optimization; Conformational analysis; Global minimum problem

• Electronic structure of molecular systems: Molecular orbitals (KS orbitals); Chemical bond; Deformation density; Localized orbitals; Population analysis; Bond-orders

•Molecular vibrations, Thermodynamics; Chemical Reactivity:Vibrational analysis; Thermodynamic properties; Modeling chemical reactions; Trantition state optimization and validation; Intrinsic Reaction Coordinate; Chemical reactivity indices; Molecular Electrostatic Potential; Fukui Functions; Single- and Two-Reactant Reactivity Indices

• Other Topics:Modelling of complex chemical processes – examples from catalysis; Molecular spectroscopy from ab initio

calculations; Advanced methods for electron correlation;Molecular dynamics; Modelling of large systems –hybrid approaches (QM/MM); Solvation models