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Near Infrared Spectroscopy of H 3 + and CH 2 +

Near Infrared Spectroscopy of H 3 + and CH 2 +. Takeshi Oka Department of Chemistry and Department of Astronomy and Astrophysics The Enrico Fermi Institute, The University of Chicago Jennifer L. Gottfried. J. Chem. Phys. 118, 10890 (2003) 121, 11527 (2004).

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Near Infrared Spectroscopy of H 3 + and CH 2 +

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  1. Near Infrared Spectroscopy of H3+ and CH2+ Takeshi Oka Department of Chemistry and Department of Astronomy and Astrophysics The Enrico Fermi Institute, The University of Chicago Jennifer L. Gottfried J. Chem. Phys.118, 10890 (2003) 121, 11527 (2004) 28th International Symposium on Free Radicals, September 5, 2005

  2. H3+ Astrophysics Rigorous theory Jupiter Galactic center Charm Interstellar M. Bawendi Ben McCall Li Wei Xu Jennifer Gottfried

  3. Barrier to Linearity 2003

  4. Vibrational Bands 6n26 6n24 3n1+2n2 6n22 2n1+3n2 6n20 n1+ 4n2 5n25 3n1+n2 5n23 5n21 2n1+2n2 4n24 n1+ 3n2 3n1 4n22 4n20 2n1+n2 n1+2n22 n1+2n20 3n23 3n21 2n1 n1+ n2 2n22 2n20 Hot bands Overtones n2 fundamental band 1980 – Oka n1 n2 Forbidden transitions Combination bands

  5. Vibrational Bands 6n26 6n24 3n1+2n2 6n22 2n1+3n2 6n20 n1+ 4n2 5n25 3n1+n2 5n23 5n21 2n1+2n2 4n24 n1+ 3n2 3n1 4n22 4n20 2n1+n2 n1+2n22 n1+2n20 3n23 Lindsay, McCall, JMS 2001 3n21 2n1 n1+ n2 2n22 2n20 22 new transitions above the barrier to linearity n1 n2 Gottfried, McCall, Oka, JCP 2003

  6. Burleigh WA-1500 Near-Infrared Spectrometer 500 MHz 19 kHz

  7. > 104 increase in Sensitivity

  8. Only “impurity”: Rydberg H2

  9. Visible H3+spectrum Chris Neese, Chris Morong

  10. PredissociationSpectrum Pseudo-low resolution convolution of experimental data[Carrington, Kennedy, J. Chem. Phys.81, 1 (1984)] Energy diagram showing significant energies of H3+ [Kemp, Kirk, McNab, Phil. Trans. R. Soc. Lond. A358, 2403 (2000)]

  11. Progress of theory Niels Bohr, 1919 First theoretical paper Henry Eyring, 1936 – 38 A series of five papers Coulson, 1936 MO theory, equilateral triangle Hirschfelder, 1938 Isosceless triangle Conroy, Christofferson, 1964 Modern ab initio Carney and Porter, 1976 Accurate VR prediction Watson, 1980 Traditional VR analysis Sutcliffe and Tennyson, 1984 Variational calculation Meyer, Botschwina, Burton, 1988 Accurate PS Neale, Miller, Tennyson, 1996 3 million lines Cencek, Rychlewski, Jaquet, Kutzelnigg, 1998 ΔPS<μH Schiffels, Alijah, Hinze, 2003 Truly first principle EVR

  12. Strong vibration-rotation interaction Strong Fermi interaction No off-diagonal Coriolis interaction Giant ℓ-doubling/resonance ν2 2521.3 cm-1 ν1 3178.3 cm-1 B0 = 43.565 cm-1 C0 = 20.605 cm-1 ζ = - 1 q = - 5.372 cm-1 Oka, Phys. Rev. Lett. 45, 531 (1980)

  13. New paradigm of spectral analysis Electronic Vibration Rotation 12 B, C, D, q… PES Obs. Variational method Variational method Meyer, Botschwina, Burton (1988) Tennyson, Sutcliffe, Miller Dinelli (London) Jacobi Lie, Frye (1992) Watson (Ottawa) r1, r2 r3 Röhse, Kutzelnigg, Jaquet, Klopper (1994) Kutzelnigg, Jaquet (Bochum) Cencek, Rychlewski, Jaquet, Kutzelnigg (1998) ΔE < 10-6 H ~ 0.2 cm-1 Wolniewicz, Hinze, Alijah (Torun, Bielefeld) hyperspherical

  14. Agreement with experiment [Alijah, Hinze, Wolniewicz, Ber. Bunsenges. Phys. Chem. 99, 251 (1995)] [Neale, Miller, Tennyson, Astrophys. J. 464, 516 (1996).] [Schiffels, Alijah, Hinze, Mol. Phys. 101, 189 (2003).] [Jaquet, Prog. Theor. Chem. Phys. 13, 503 (2003).] [Alijah, private communication (2003).] empirical correction for nonadiabatic effects purely ab initio calculation!

  15. Expectation Values (Watson) J=0-2, J=3-5, J=6-10, J=11-15, J=16-20

  16. Big picture H2:W. Kołos, L. Wolniewicz 1964 – 1975 J. Mol. Spectrosc. 54, 303 (1975) H3+:Schiffels, Alijah, Hinze, Mol. Phys. 101, 175, 189 (2003) Non-adiabatic and QED corrections missing H5+ What’s next ? ([H2]2) CH5+ Saporoschenko JCP 42, 2760 (1964) Lindsay, McCall, JMS 210, 60 (2001) JCP 86, 5072 (1987) 72 unassigned lines

  17. InterstellarChemistry

  18. The enigma of CH+ chemistry CH++ H → C+ + H2 + 0.4 eV CH++ H2→ CH2+ + H + 1.7 eV CH+ emission from the Red Rectangle

  19. ~ A2B1 Vbend(r)/cm-1 ~ X2A1 r/degrees 2Πustate split by Renner – Teller effect Isoelectronic to BH2 Bender and Schaefer 1971 Carter and Handy 1984 Reuter and Peyerimhoff 1992 Kraemer, Jensen, Bunker 1994 Jensen, Brum, Kraemer, Bunker 1995 Osmann, Bunker, Jensen, Kraemer 1997 Bunker, Chan, Kraemer, Jensen 2001 Herzberg, Johns, 1967 Rösslein, Gabrys, Jagod, Oka 1992 Willitsch, Imbach, Merkt, 2002 Willitsch, Merkt 2003

  20. H2 H2 H2 C+ CH+ CH2+ CH3+ CH4+ CH5+ -H -H -H Chemistry of CH2+ He* + CH4 CH4+ CH3+ CH2+ Production, Penning ionization

  21. Chemical Discrimination CH2+ H2* “grass”

  22. Π←Σ(0, 8, 0) ← (0, 0, 0) Ã(0,3,0)1X̃(0,0,0)0 Ka

  23. Σ←Π(0, 9, 0) ← (0, 1, 0) Ã(0,4,0)0X̃(0,0,0)1

  24. Δ← Π(0, 9, 0) ←(0, 1, 0) Ã(0,3,0)2X̃(0,0,0)1 unassigned lines

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