Galen Sedo, Jane Curtis, Kenneth R. Leopold Department of Chemistry, University of Minnesota The...
-
Upload
andra-kelly -
Category
Documents
-
view
216 -
download
1
Transcript of Galen Sedo, Jane Curtis, Kenneth R. Leopold Department of Chemistry, University of Minnesota The...
Galen SedoGalen Sedo, Jane Curtis, Kenneth R. Leopold, Jane Curtis, Kenneth R. Leopold
Department of Chemistry, University of MinnesotaDepartment of Chemistry, University of Minnesota
The Dipole Moment of the The Dipole Moment of the Sulfuric Acid MonomerSulfuric Acid Monomer
Sulfuric Acid Aerosols• A principle source of sulfate-containing
atmospheric particles
• High affinity for water and a high rate of nitrogen species uptake
Investigating Sulfuric Acid SystemsInvestigating Sulfuric Acid Systems
Nucleation Theory• Homogeneous and Heterogeneous particle growth
• Ion-induced and ion-mediated nucleation theory
• Charge-dipole interactions
H2SO4b
2.725(15) D
H2SO4-H2Oa
3.052(17) D
a) Brauer, C. S.; Sedo, G.; Leopold, K. R. Geophys. Res. Lett. 33 (2006) L23805, doi:10.1029/2006GL028110.
b) Kuczkowski, R. L.; Suenram, R. D.; Lovas, F. J. Journal of the American Chemical Society 1981, 103, 2561.
Previous Dipole Moment WorkPrevious Dipole Moment Work
H2SO4b
2.725(15) D
2.817 D
H2SO4-H2Oa
3.052(17) D
2.147 D
a) Brauer, C. S.; Sedo, G.; Leopold, K. R. Geophys. Res. Lett. 33 (2006) L23805, doi:10.1029/2006GL028110.
b) Kuczkowski, R. L.; Suenram, R. D.; Lovas, F. J. Journal of the American Chemical Society 1981, 103, 2561.
c) Al Natsheh, A; Nadykto, A. B.; Mikkelsen, K. V.; Yu, F.; Ruuskanen, J. J. Phys. Chem. A 2004, 108, 8914.
Previous Dipole Moment WorkPrevious Dipole Moment Work
PW91PW91/TZPc
0.905 D(29.7 %)
-0.092 D(-3.4 %)
H2SO4b
2.725(15) D
2.817 D
3.147 D
H2SO4-H2Oa
3.052(17) D
2.147 D
2.965 D
a) Brauer, C. S.; Sedo, G.; Leopold, K. R. Geophys. Res. Lett. 33 (2006) L23805, doi:10.1029/2006GL028110.
b) Kuczkowski, R. L.; Suenram, R. D.; Lovas, F. J. Journal of the American Chemical Society 1981, 103, 2561.
c) Al Natsheh, A; Nadykto, A. B.; Mikkelsen, K. V.; Yu, F.; Ruuskanen, J. J. Phys. Chem. A 2004, 108, 8914.
Previous Dipole Moment WorkPrevious Dipole Moment Work
PW91PW91/TZPc
0.905 D(29.7 %)
-0.092 D(-3.4 %)
0.087 D(2.9 %)
-0.692 D(-25.4 %)
MP2/aug-cc-pVQZa
Mirror
Antenna
Argon passed over a sample of polymerized SO3
Backing Pressure 25 psig
Microwave
Electronics
Computer
14732.5 14733 14733.5 14734 14734.5 14735
Frequency (MHz)Spectrum
Fabry-Perot Cavity
Diffusion Pump
Pulsed
Nozzle
Mirror
The Pulsed Nozzle FTMW Spectrometer
Mirror
Antenna
Argon passed over a sample of polymerized SO3
Backing Pressure 25 psig
Microwave
Electronics
Computer
14732.5 14733 14733.5 14734 14734.5 14735
Frequency (MHz)Spectrum
Fabry-Perot Cavity
Diffusion Pump
Pulsed
Nozzle
Mirror
The Pulsed Nozzle FTMW Spectrometer
Series 9PulsedSolenoidValve
Needle Adaptor
• Stainless Steal Needle Dimensions ID = 0.016" Length = 0.205"
• Argon bubbled through H2O at a rate of 10 sccm.
Diffusion Pump
Fabry-Perot Cavity
The Pulsed Nozzle FTMW Spectrometer
Mirror
Fabry-Perot Cavity
Diffusion Pump
Mirror
Diffusion Pump
Fabry-Perot Cavity
The Pulsed Nozzle FTMW Spectrometer
1. A potential of up to 10,000 V(5,000 V/plate)
2. Calibrated the plate spacing before and after collecting data using the Ar-SO3 complex [ = 0.2676(3) D]
• Checked the calibration method using OCS
lit = 0.7152(2) D
obs = 0.7157(16) D
DM = 0
y = 1.1674E-04x - 7.7449E-04
R2 = 1.0000E+00
0.0
0.5
1.0
1.5
2.0
0 5000 10000 15000
e2 (V
2/cm
2)
Dn
(MH
z)Zero Field and 37 Stark-shifted Frequencies
The The DDM = 0 Stark Component of theM = 0 Stark Component of the
111010 ← 0 ← 00000 Transition Transition
10184.250 10184.750 10185.250 10185.750 10186.250 10186.750
10184.250 10184.750 10185.250 10185.750 10186.250 10186.75010184.250 10185.250 10186.250
Frequency [MHz]
e = 0 V/cm
e = 76.5 V/cm
Dnmax = 1.749 MHz
emax = 122.3 V/cm
D|M| = 1
y = 5.1046E-05x - 5.8754E-04
R2 = 1.0000E+00
0.0
0.5
1.0
1.5
2.0
0 10000 20000 30000
e2 (V2/cm2)
Dn
(MH
z)Zero Field and 54 Stark-shifted Frequencies
Dnmax = 1.721 MHz
emax = 183.5 V/cm10184.250 10184.750 10185.250 10185.750 10186.250 10186.750
10184.250 10184.750 10185.250 10185.750 10186.250 10186.750
e = 0 V/cm
e = 76.5 V/cm
10184.250 10185.250 10186.250
Frequency [MHz]
The The D|D|M| = 1 Stark Component of theM| = 1 Stark Component of the
111010 ← 0 ← 00000 Transition Transition
a) Kuczkowski, R. L.; Suenram, R. D.; Lovas, F. J. “Microwave Spectrum, Structure, and Dipole Moment of Sulfuric Acid.” Journal of the American Chemical Society 1981, 103, 2561-2566.
Sulfuric Acid Molecular ConstantsSulfuric Acid Molecular Constantsaa
a) Kuczkowski, R. L.; Suenram, R. D.; Lovas, F. J. “Microwave Spectrum, Structure, and Dipole Moment of Sulfuric Acid.” Journal of the American Chemical Society 1981, 103, 2561-2566.
Sulfuric Acid Transition FrequenciesSulfuric Acid Transition Frequenciesaa
H = Hrot + HQ + He
He = -• e
c = tot = 2.9643(67) D
H = Hrot + HQ + He
He = -• e
110 ← 000
c = tot = 2.9643(67) D
643 ← 533
c = tot = 2.725(15) D
Dn = (ac + bcM2)e2c2
ac = 2.4048 x 10-8
bc = -3.8759 x 10-6
A 5160.5951(36)B 5024.5405(33)C 4881.025(13)D
J 0.002522(27)D
JK -0.00516(86)D
K 0.005214(74)d
J -0.000413(17)d
K 0.003099(65)
Molecular Constants for the H2SO4 Monomer.
(a) All values are in MHz.
643 ← 533
c = tot = 2.725(15) D
664343 ← 5 ← 53333 Stark Coefficients Stark Coefficients
M = 1
-1.0
-0.8
-0.6
-0.4
-0.2
0.0
0 5000 10000 15000 20000 25000
e2 [V/cm]
Dn
[MH
z]
y = -3.3742E-05x – 4.6141E-04
R2 = 1.0000
M = 0
0.000
0.001
0.002
0.003
0.004
0.005
0 5000 10000 15000 20000 25000
e2 [V/cm]
Dn [
MH
z]
y = 2.112E-07x – 5.694E-05
R2 = 1.000
643 ← 533
c = tot = 2.725(15) D
ac = 2.4048 x 10-8
bc = -3.8759 x 10-6
110 ← 000
c = tot = 2.9643(67) D
ac = 2.4032 x 10-8
bc = -3.8640 x 10-6
Error AnalysisError Analysis
Three Primary Sources of Experimental Error
1. Least Squares Analysis ls = 2.96434 D
Dls = 0.00023 D
Three Primary Sources of Experimental Error
1. Least Squares Analysis ls = 2.96434 D
Dls = 0.00023 D
2. Plate Spacing dplate = 32.702 cm
Dplate = 0.064 cm
Error AnalysisError Analysis
22
D
DD
plate
plate
ls
lslstotal d
Error AnalysisError Analysis
Dd SOAr
SOAr
plate
plate
ls
lslstotal 0067.0
222
3
3
D
D
DD
Three Primary Sources of Experimental Error
1. Least Squares Analysis ls = 2.96434 D
Dls = 0.00023 D
2. Plate Spacing dplate = 32.702 cm
Dplate = 0.064 cm
3. Calibration Standard Ar-SO3 = 0.2676 D
DAr-SO3 = 0.0003 D
This Work 2.9643(67) D
Kuczkowski, Suenram, & Lovas 2.725(15) D0.239 D
Comparison of the Experimental and Comparison of the Experimental and Theoretical Dipole MomentsTheoretical Dipole Moments
PW91PW91/aug-cc-pV(Q+d)Z 2.9520 D
MP2/aug-cc-pV(Q+d)Z 3.4416 D
0.0
5.0
10.015.0
20.0
25.0
30.0
HF MP2 B3LYP PW91
Theory/aug-cc-pVTZ
|% E
rror
|
This Work
Literature
Comparison of the Experimental and Comparison of the Experimental and Theoretical Dipole MomentsTheoretical Dipole Moments
This Work 2.9643(67) DPW91PW91/aug-cc-pV(Q+d)Z 2.9520 DMP2/aug-cc-pV(Q+d)Z 3.4416 D
Brauer et al. 3.052(17) DPW91PW91/aug-cc-pVQZ 2.407 DMP2/aug-cc-pVQZ* 2.965 D
H2SO4
H2SO4-H2O
* Single-point calculation done at the aug-cc-pVTZ geometry, taken from Brauer et al.
0.0
5.0
10.0
15.0
20.0
25.0
HF MP2 B3LYP PW91
Theory/aug-cc-pVTZ
|% E
rror
|
Sulfuric Acid
Monohydrate
ConclusionsConclusions
1. The dipole moment of the sulfuric acid monomer has been refined using Fourier transform microwave spectroscopy.
• 91 Stark-shifted frequencies were collect for the 110 ← 000 rotational transition.
• The newly measured value, 2.9643(67) D, represents an increase of approximately 0.24 D over the previously published value.
2. The dipole moments of the sulfuric acid monomer and mono-hydrate were calculated using both ab initio and Density Functional Theory.
• The calculated dipole moments show convergence with increasing basis set size.
• The agreement between the measured experimental values and those of theory various drastically with the method employed.
• Dr. Kenneth Leopold
• Jane Curtis
• Dr. Carolyn Brauer
Acknowledgements
Funding
• National Science Foundation (NSF)
• Petroleum Research Fund (PRF)
• Minnesota Supercomputing Institute (MSI)
J' K-1' K+1' J" K-1" K+1" nobs
ncalc
nobs-ncalc
AssignedError n
obs-ncalcc
1 1 0 0 0 0 10185.126 10185.127 -0.001 0.005 -----6 3 3 5 2 3 60668.59 60668.65 -0.06 0.15 -0.066 4 2 5 3 2 60861.50 60861.43 0.07 0.15 0.066 1 5 5 0 5 60935.35 60934.87 0.48 0.15 0.476 3 4 5 2 4 60939.80 60940.06 -0.26 0.15 -0.276 2 5 5 1 5 60946.00 60945.72 0.28 0.15 0.276 4 3 5 3 3 61060.32 61060.53 -0.21 0.15 -0.226 5 1 5 4 1 61317.72 61317.35 0.37 0.15 0.346 5 2 5 4 2 61353.12 61353.36 -0.24 0.15 -0.278 3 5 7 2 5 81056.65 81056.47 0.18 0.15 0.188 5 3 7 4 3 81066.90 81066.92 -0.02 0.15 -0.028 4 5 7 3 5 81212.24 81212.14 0.10 0.15 0.09
10 5 5 9 4 5 101080.17 101080.21 -0.04 0.15 -0.0510 6 4 9 5 4 101267.30 101267.42 -0.12 0.15 -0.1110 4 6 9 3 6 101294.00 101294.46 -0.46 0.15 -0.4610 5 6 9 4 6 101475.20 101475.32 -0.12 0.15 -0.1210 3 7 9 2 7 101480.86 101480.71 0.15 0.15 0.1510 4 7 9 3 7 101503.07 101503.44 -0.37 0.15 -0.3710 6 5 9 5 5 101574.71 101574.86 -0.15 0.15 -0.1610 1 9 9 0 9 101594.99 101595.07 -0.08 0.15 -0.0910 7 3 9 6 3 101775.30 101775.42 -0.12 0.15 -0.1210 7 4 9 6 4 101852.61 101852.67 -0.06 0.15 -0.0710 8 2 9 7 2 102221.46 102221.32 0.14 0.15 0.1310 8 3 9 7 3 102227.85 102227.76 0.09 0.15 0.0810 10 1 9 9 1 103008.75 103008.82 -0.07 0.15 -0.0911 6 5 10 5 5 111209.35 111209.35 0.00 0.15 0.0011 5 6 10 4 6 111268.10 111267.94 0.16 0.15 0.1611 4 7 10 3 7 111533.90 111533.79 0.11 0.15 0.1211 5 7 10 4 7 111612.31 111612.29 0.02 0.15 0.0211 7 4 10 6 4 111617.32 111617.21 0.11 0.15 0.1211 6 6 10 5 6 111629.15 111629.04 0.11 0.15 0.1011 3 8 10 2 8 111661.00 111660.40 0.60 0.15 0.6111 4 8 10 3 8 111667.05 111667.42 -0.37 0.15 -0.3711 1 10 10 0 10 111757.44 111757.51 -0.07 0.15 -0.0511 7 5 10 6 5 111817.39 111817.21 0.18 0.15 0.1811 8 3 10 7 3 112126.95 112126.89 0.06 0.15 0.0711 8 4 10 7 4 112156.53 112156.62 -0.09 0.15 -0.0811 10 1 10 9 1 112937.95 112938.13 -0.18 0.15 -0.2011 11 1 10 10 1 113327.41 113327.29 0.12 0.15 0.12
(b) All transition assignments and frequencies, except the 110 ← 000, are those reported by Kuczkowski et al .(c) Original nobs - ncalc values reported by Kuczkowski et al .
Rotational Transitions for the H2SO4 monomer.a,b
(a) All frequencies are in MHz.