Eirík´s project(?)

CH3I:

agust,www,...rempi/ch3i/PPT-050112ak.ppt(https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PPT-050112ak.ppt )agust,heima,...REMPI/CH3I/PXP-050112ak.pxphttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxp

1)compound: availability and physical properties2)Absorption spectra on www3)Papers4)Energetics(?)

Eiríks project

1) CH3I:

Svana´s e-mail, 071211:

http://en.wikipedia.org/wiki/Methyl_iodide :

liquid

Vapor pressure:

CRC: 1 mm 10 40 100 400 760 mp

S -45.8oC -24.2 -7.0 +25.3 42.4 -64.4

Vapor pressure = 100 Torr for -7 oC

See cooling baths: http://www.chem.orst.edu/carter/Baths.html

ATH 1

ATH 2

500

400

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200

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0

x10-1

8

300250200150

agust,heima,...REMPI/CH3I/PXP-050112ak.pxp; Lay:0, Gr:0

ATH 1https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf

(2007)

agust,heima,...REMPI/CH3I/PXP-050112ak.pxp; Lay:0, Gr:0

2.5

2.0

1.5

1.0

0.5

0.0

-0.5

x10-1

8

300280260240

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150

100

50

0

x10-1

8

240220200180160140120

ATH 2

agust,heima,...REMPI/CH3I/PXP-050112aka.pxp; Lay:0, Gr:0

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cp365-109-09.pdf

Absorption references:

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cp365-109-09.pdf

Absorption references: https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf

Absorption references: https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf

See tables 4-7 inThe paper

Check REMPI work-by Donovan et al.-references in CH3Br REMPI paper etc.

With repect to Rydberg state structure.

Papers: See also Eirik´s folder

Rydberg states: https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp99-836-93.pdf RESONANCE-ENHANCED MULTIPHOTON IONIZATION PHOTOELECTRON-SPECTROSCOPY ON NANOSECOND AND PICOSECOND TIME SCALES OF RYDBERG STATES OF METHYL-IODIDE

Abstract: Rydberg states of methyl iodide have been investigated using resonance enhanced multiphoton ionization in combination with photoelectron spectroscopy with nanosecond and picosecond laser pulses. The study of the ns (6 less-than-or-equal-to n less-than-or-equal-to 10) Rydberg states in two-, three-, and four-photon excitations has resulted in an unambiguous identification of state [1] in the 7s and 8s Rydberg states. As a consequence, it is concluded that the transition to 6s[1] in two- and three-photon excitations is anomalously weak. The application of photoelectron spectroscopy to identify the electronic and vibrational nature of a resonance has led to a major reinterpretation of the excitation spectrum of the 6p Rydberg state in two-photon excitation. In many of the recorded photoelectron spectra anomalous electrons are observed, which derive from a one-photon ionization process. This process is suggested to find its origin in the mixing of 6p and 7s character into higher-lying Rydberg states. The major difference between resonance enhanced multiphoton ionization photoelectron spectroscopy with nanosecond and picosecond lasers is found in a less effective dissociation of the molecule in the picosecond experiments.

...Ry states, state mixing, vibr. Freq. Modes, (2+1)REMPI spectra and assignments of Rydb. states

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cpl156-151-89.pdf

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cpl173-257-90.pdf

(2+1)REMPI..3p Ry

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jpc86-60-82.pdf

Shows 1) mass spectra and 2) energetics

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cpl345-57-01.pdf

Bond energies, ..

1) https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cpl516-23-11.pdf Isotopic effect in the (2+1) REMPI spectra of (13)C-substituted methyl iodide for UV selective dissociation

To investigate a possible means of achieving isotopic enrichment of methyl iodide (CH(3)I), we studied the 6s Rydberg states of (13,12)CH(3)I by (2+1) resonance-enhanced multiphoton ionization. For 3; 3(1)(0) band (v3 hot band) excitation ( at a full width at half maximum of 14 cm (1)), we observed a well-resolved isotope shift of +16 cm (1). The band shape, which has a broad shoulder on the red side and an abrupt decrease on the blue side, indicates that this resonance is ideal for enriching the concentration of the desired lighter isotope (the isotopomer). (C) 2011 Elsevier B.V. All rights reserved.

2) https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jms257-200-09.pdf Photoelectron imaging of 8p Rydberg states of atomic iodine following methyl iodide A-band decomposition

Photoelectron imaging technique has been applied to study (2 + 1) REMPI of atomic iodine through 8p Rydberg states around 253 nm. Full three-dimensional state-specific speed and angular distributions of the photoelectrons were recorded. The branching ratios among the different I(+) levels revealed that the perturbation on ((3)P(2))8p series is particularly large among the ((3)P(2))np series. The violation of core-conserving ionization is attributed to the interactions between the ((3)P(2))8p and ((1)D(2))6p series. The photoelectron angular distributions were found to be well characterized by P(2)(cos theta) and P(4)(cos theta). A relatively high positive beta(2) and a relatively low beta(4) observed in (2 + 1) REMPI process indicated that the ionization process can be approximately considered as single-photon ionization via the weakly aligned ((3)P(2))8P intermediate states. (C) 2009 Elsevier Inc. All rights reserved.

Less useful but new papers:

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jams2-93-11.pdf

Now we need to look at the energetics, analogous to that for CH2Br2:http://www3.hi.is/~agust/rannsoknir/rempi/ch2br2/PPT-010211ak.ppt(See slides 6 -11)

https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cp365-109-09.pdf

Fig 10:

NIST

IE:

76945.25 cm-1

http://www.sciencedirect.com/science/article/pii/S0009261401008648

19195.9852 cm-1

CH3:

CH3I D:

2.38eV http://www.sciencedirect.com/science/article/pii/S0009261401008648 19195.9874cm-1 Factors:

f1: 8.36E+01cm-1 / (kJ mol-1)

f2: 3.50E+02cm-1 / (kcal mol-1) f3: 8065.54093cm-1/eV E(6s) = 54633.46cm-1 E(4P;5s)+D= 73829.45cm-1 IE(CH3I)= 9.54eV NIST IE(CH3I)= 76945.26047cm-1 IE(I)= 84295.1cm-1 http://physics.nist.gov/cgi-bin/ASD/energy1.pl E(S/O;I)= 7602.97cm-1 http://physics.nist.gov/cgi-bin/ASD/energy1.pl

E(CH3+I*(1/2))= 26798.95741cm-1 E(CH3+I+ + e)= 103491.0874cm-1 IE(CH3) = 9.84eV 79364.92275cm-1 E(CH3+ + e + I) 98560.91016cm-1 EA(I) = 3.0590463eV http://en.wikipedia.org/wiki/Electron_affinity_%28data_page%29 24672.8631cm-1E(CH3+ + I-)= 73888.04703cm-1 E(I+)-E(I*)= 76692.13cm-1

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4.03.53.02.52.01.51.0

CH3 + I; 19195.9874

CH3 + I*; 26798.95741

CH3 + I**(min); 73829.45

CH3+ + e + I; 98560.91016

CH3 + I+ + e; 103491.0874

CH3I

CH3I+ + e; 76945.26047

cm-1

https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxp

https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxp

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43210