1. Eirík´s project(?) CH 3 I: agust,www,...rempi/ch3i/PPT-050112ak.ppt ( https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PPT-050112ak.ppt ) https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PPT-050112ak.ppt agust,heima,...REMPI/CH3I/PXP-050112ak.pxp https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxphttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxp (energetics and abs. spectrum) https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/XLS-230112ak.xlshttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/XLS-230112ak.xls (energetics) 1)compound: availability and physical properties 2)Absorption spectra on www 3)Papers 4)Energetics(?)

2. Eiríks project 1) CH 3 I: Svana´s e-mail, 071211:

3. http://en.wikipedia.org/wiki/Methyl_iodidehttp://en.wikipedia.org/wiki/Methyl_iodide : liquid Vapor pressure: CRC: 1 mm1040100400760mp S-45.8oC-24.2-7.0+25.342.4-64.4 Vapor pressure = 100 Torr for -7 o C See cooling baths:http://www.chem.orst.edu/carter/Baths.html

11. ATH 1 ATH 2

12. agust,heima,...REMPI/CH3I/PXP-050112ak.pxp; Lay:0, Gr:0 ATH 1 https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf (2007)

13. agust,heima,...REMPI/CH3I/PXP-050112ak.pxp; Lay:0, Gr:0 ATH 1

14. 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

15. 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

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

17. Absorption references: https://notendur.hi.is/agust/rannsoknir/papers/CH3X/cp331-232-07.pdf See tables 4-7 in The paper

18. Check REMPI work -by Donovan et al. -references in CH3Br REMPI paper etc. With repect to Rydberg state structure.

19. Papers: See also Eirik´s folder Rydberg states: https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp99-836-93.pdf 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

20. 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

21. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jpc86-60-82.pdf Shows 1) mass spectra and 2) energetics

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

23. 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.pdfhttps://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:

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

25. 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)

26. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/cp365-109-09.pdf Fig 10:

27. NIST IE: 76945.25 cm-1

28. http://www.sciencedirect.com/science/article/pii/S0009261401008648 19195.9852 cm-1

29. CH3:

30. CH3I D: 2.38eVhttp://www.sciencedirect.com/science/article/pii/S000926140100864819195.9874cm-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-1E(4P;5s)+D=73829.45cm-1 IE(CH 3 I)=9.54eVNIST IE(CH 3 I)=76945.26047cm-1 IE(I)=84295.1cm-1http://physics.nist.gov/cgi-bin/ASD/energy1.pl E(S/O;I)=7602.97cm-1http://physics.nist.gov/cgi-bin/ASD/energy1.pl E(CH 3 +I*(1/2))=26798.95741cm-1 E(CH 3 +I + + e)=103491.0874cm-1 IE(CH 3 ) =9.84eV79364.92275cm-1 NIST E(CH 3 + + e + I)98560.91016cm-1 EA(I) =3.0590463eVhttp://en.wikipedia.org/wiki/Electron_affinity_%28data_page%2924672.8631cm-1 E(CH 3 + + I-)=73888.04703cm-1 E(I + )-E(I*)=76692.13cm-1 https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/XLS-230112ak.xls

31. CH 3 + I; 19195.9874 CH 3 + I*; 26798.95741 CH 3 + I**(min); 73829.45 CH 3 + + e + I; 98560.91016 CH 3 + I + + e; 103491.0874 CH 3 I CH 3 I + + e; 76945.26047 cm -1 https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxp

32. CH 3 + I; 19195.9874 CH 3 + I*; 26798.95741 CH 3 + I**(min); 73829.45 CH 3 + + e + I; 98560.91016 CH 3 + I + + e; 103491.0874 CH 3 I CH 3 I + + e; 76945.26047 Abs. spectrum (1) (2) (3) (4) (n) = number of photons 70000 55000

33. CH 3 + + e + I; 65707.27 cm-1..threshold hv(Laser)=16426.82 (608.7606 nm) CH 3 + I + + e; 68994.06 cm-1..threshold: hv(Laser) = 17248.51 (579.7601 nm) https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-230112ak.pxp 70000 cm -1

34. REMPI spectra and assignments from the literature:

35. n:22222222222n:22222222222 s -States and spectra observed in Two-photon REMPI https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp99-836-93.pdf n = number of resonance excitation photons

36. n:22222222222n:22222222222 s -States and spectra observed in Two-photon REMPI https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp99-836-93.pdf

37. n:22222222222n:22222222222 s -States and spectra observed in Two-photon REMPI https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp99-836-93.pdf

38. : 5800064000 2hv https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp99-836-93.pdf p -States and spectra observed in Two-photon REMPI

39. p states spectra observed in (2+n) REMPI s states spectra observed in (2+n) REMPI https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250112ak.pxp Ca. Spectral region for R590! 66640-69480

40. p states spectra observed in (2+n) REMPI s states spectra observed in (2+n) REMPI https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250112ak.pxp 64000 58000

41. 64000 58000 62000 60000 p states spectra observed in (2+n) REMPI Comparison of absorption and REMPI spectra: https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250112ak.pxp

42. 72900 72500

44. CH 3 + I; 19195.9874 CH 3 + I*; 26798.95741 CH 3 + I**(min); 73829.45 CH 3 + + e + I; 98560.91016 CH 3 + I + + e; 103491.0874 CH 3 I CH 3 I + + e; 76945.26047 Abs. spectrum (1) (2) (3) (4) (n) = number of photons 70000 55000 https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-260112ak.pxp x100 The A-band

45. CH 3 I + + e; 76945.26047 Abs. spectrum (1) (2) (n) = number of photons 70000 55000 x100 https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-260112ak.pxp The A-band n  *(C-I) 65707.27 cm-1) 68994.06 cm-1

46. CH3+ 1D REMPI uncorrected Absorption spectrum 2hv https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/Experiment-260112vhwak.pxp

47. ??? cm -1 pnt

48. IDEA!: an I 2 + mass peak observed could be due to a molecular dimer (CH 3 I) 2 ERGO: let´s see the effect of less cooling, i.e. 1)less % argon 2) less backing pressure. Let´s check the literature Literature: 1)http://www.chemthes.com/entity_datapage.php?id=1851 : Van der Waals complexeshttp://www.chemthes.com/entity_datapage.php?id=1851 2)http://jcp.aip.org/resource/1/jcpsa6/v97/i1/p189_s1?isAuthorized=no https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp97-189-92.pdf : “Ground electronic state I 2 is formed from the photolysis of methyl iodide dimers”http://jcp.aip.org/resource/1/jcpsa6/v97/i1/p189_s1?isAuthorized=no https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp97-189-92.pdf 3)Sjá meira neðar See example for effect of buffer gas (rare gas) on jet cooling next slide:

49. Largest molecular density= molecular beam Small molecular density= molecular diffusion medium molecular density Skimmer; Not used in our case Beam axis http://www.nature.com/nphys/journal/v4/n8/box/nphys1031_BX1.htmlhttp://www.nature.com/nphys/journal/v4/n8/box/nphys1031_BX1.html :

50. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jppbA100-9-96.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jppbA100-9-96.pdf :

51. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jpc100-11559-96.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jpc100-11559-96.pdf : http://jcp.aip.org/resource/1/jcpsa6/v97/i1/p189_s1?isAuthorized=nohttp://jcp.aip.org/resource/1/jcpsa6/v97/i1/p189_s1?isAuthorized=no & https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp97-189-92.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp97-189-92.pdf :

52. 1 mm1040100400760 PTorr S-45.8-24.2-725.342.4 t/oC 227.35248.95266.15298.45315.55T/K 0.00439850.0040170.0037570.0033510.0031691/T (K-1) 2.302585093.6888794.605175.9914656.633318ln(p) 1/T (K-1) 2.302585090.434294 3.688879450.271085 4.605170190.217147 5.991464550.166904 6.633318430.150754 1/T (K-1) Ln(p) https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/XLS-270112ak.xlshttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-270112ak.pxp ln(p) vs 1/T is nonlinear suggesting less importance of dimers as temperature rizes.

53. This could mean that CH 3 I dimers are even formed in the vapour above the trap when cooled with CCl 4 slash bath (-23 o C)!! --further suggesting that it might be better to use less cooling for the trap: How about to use cold water only (analogous to that used for CH 2 Br 2 earlier) ???

54. https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-100212ak.pxp CH3+ 1D REMPI uncorrected Absorption spectrum 2hv No clear correspondance between REMPI and absorption spectra in this region

55. CH3+ 1D REMPI uncorrected Absorption spectrum 2hv What on earth is that??? https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-100212ak.pxp

56. CH3+ 1D REMPI uncorrected Absorption spectrum 2hv This looks like P, Q and R brances Of symmetric top: seen next slide https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-100212ak.pxp  = 19.16..18.36..16.8 19.84 19.84 19.84

57. IR róf topsamhverfra sameinda / IR spectra for symmetric top molecules: CH 3 I: Topsamhv. http://notendur.hi.is/agust/kennsla/ee10/eeb/PPT/IR%20rof.ppthttp://notendur.hi.is/agust/kennsla/ee10/eeb/PPT/IR%20rof.ppt: B: Fundamentals of Molecular Spectroscopy eftir C.N. Banwell og E.M. McCash, (McGraw-Hill, 4. útg. 1994)

59. Are these all iodine atomic lines? What transitions are these, Eiríkur? https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-100212ak.pxp hv(laser)

60. Same molecular peak seen in the I+ and CH3+ spectra hv(laser) https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-100212ak.pxp C atomic lines Small but significant peak

61. https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250312ak.pxphttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250312ak.pxp og 69852.92828 cm-1 ftp://130.208.167.52/Data/CH3I/Calibartion Work/calibration/ allt I cal, 16220_17510 funky17540_17650-210312.pxp allt I cal, 16220_17510 funky17540_17650-210312.pxp CH3+ REMPI

62. 70626.462 cm-1 https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250312ak.pxphttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250312ak.pxp og ftp://130.208.167.52/Data/CH3I/Calibartion Work/calibration/ allt I cal, 16220_17510 funky17540_17650-210312.pxp allt I cal, 16220_17510 funky17540_17650-210312.pxp 773.5337 cm-1 8.408 8.4 CH3+ REMPI

63. https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250312ak.pxphttps://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-250312ak.pxp og ftp://130.208.167.52/Data/CH3I/Calibartion Work/calibration/ allt I cal, 16220_17510 funky17540_17650-210312.pxp allt I cal, 16220_17510 funky17540_17650-210312.pxp I+ REMPI

64. Symmetric top: http://www.hi.is/~agust/kennsla/ee05/ee405/rotst.ppt https://notendur.hi.is/agust/kennsla/ee10/ees10/snthrep.htm

65. http://webbook.nist.gov/cgi/cbook.cgi?ID=C2229074&Units=SI&Mask=800#Electronic-Spechttp://webbook.nist.gov/cgi/cbook.cgi?ID=C2229074&Units=SI&Mask=800#Electronic-Spec: 69852.92828 cm-1 OUR CH3+ REMPI spectrum At 69852.9 is Due to CH3 !!!! Check this reference

66. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdf :

67. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdf : 69852.92828 cm-1 Ours NB!:  K = 0

68. https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdf : Ground state Excited state Coupling terms NB!:  K = 0

69. ..but what about this spectrum: It must be because of CH3 There is no reported electronic state for CH3 at this wavenumber The spacing of 773.5 cm-1 between the two CH3+ spectra suggests that it could be A vibrationally excited state 70626.462 cm-1 773.5337 cm-1

70. Could be the a2 2 (OPLA) vibrational mode Let´s check references out ‐ of ‐ plane large amplitude (OPLA)-mode = umbrella modes http://webbook.nist.gov/cgi/cbook.cgi?ID=C2229074&Units=SI&Mask=800#Electronic-Spechttp://webbook.nist.gov/cgi/cbook.cgi?ID=C2229074&Units=SI&Mask=800#Electronic-Spec:

71. NB!: OPLA modes can be significantly different for excitede states than for The ground state, thus: NIST: http://webbook.nist.gov/cgi/cbook.cgi?ID=C2229074&Units=SI&Mask=800#Electronic-Spechttp://webbook.nist.gov/cgi/cbook.cgi?ID=C2229074&Units=SI&Mask=800#Electronic-Spec:...but these seem, generally to be the lowest numbers

72. O PQ R S Our spectrum simulated for parameters in https://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdfhttps://notendur.hi.is/agust/rannsoknir/papers/CH3X/CH3I/jcp89-3986-88.pdf : Calculations were performed in https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-020412ak.pxp https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/XLS-020412ak.xls 69852.92828 cm-1

73. Since the Q branch in the 70626.462 cm -1 system is degraded to red (low wavenumber) opposide of what is found for the 69852.92828 cm -1 system (slide 72) it suggest that B´< B´´ opposide of what is found for the 69852.92828 cm -1 sysem (see slide 68) where B´= 9.90 cm -1 and B” = 9.577..cm -1 70626.462 cm -1 First attempts to simulate the vibrationally excited band of CH3:

74. 9.57789 = B” 0.0007699 =D N ” -0.0001358 =D NK ” 9 =B´ 0.00107 =D N ´ -0.00212 =D NK ´ 70627.2 “= 0 -0.088 =  C 0 =  DK R Q S P O  K = 0 70626.462 cm -1 https://notendur.hi.is/agust/rannsoknir/rempi/ch3i/PXP-020412aka.pxp