A spectroscopic database for acetylene between 5850 and 9415 cm–1 A .Campargue1, O.L. Lyulin 2 1Univ. Grenoble Alpes, CNRS France 2 Institute of Atmospheric Optics Tomsk Russia

C2H2 Stretch-Bend System Prototype triple C-C bond species n1 =3372 cm-1 1. C-H symmetric stretch 2. C-C stretch 3. C-H antisym- metric stretch 4. Trans bend 5. Cis bend Vibrational angular momenta l4, l5 n2 = 1975 cm-1 n3 = 3289 cm-1 n4 = 608 cm-1 n5 = 729 cm-1 g/u symmetry 3 approximately conserved (and rigorously conserved in Heff) polyad numbers due to a frequency ratio M. Kellman Columbus, Ohio June 22, 2007 dynamical aspects, IVR, planets, carbon stars…

VCH 8 23813 cm-1 7 21166 6 18430 5 15600 4 12675 3 9640 2 6556 1 3281 23813 cm-1 9640 cm-1 6556 cm-1 3282 cm-1 Hall PhD thesis 1984

V=2 V=3 FTS spectrum from J. Vander Auwera at ULB (L= 48.3 m)

CRDS V=2 V=3 FTS ULB FTS USTC FTS ULB

C2H2 Stretch-Bend System w1 : w2 : w3 : w4 : w5 = 3372:1975:3289:608:729 ~ 5:3:5:1:1 1. C-H symmetric stretch 2. C-C stretch 3. C-H antisym- metric stretch 4. Trans bend 5. Cis bend Vibrational angular momenta l4, l5 K11/33 P= 5V1+3V2+5V3+V4+V5 K3/145 K1/244 K1/255 K14/35 … {P, e/f, u/g, i} DD-I, l, DD-II g/u symmetry 3 approximately conserved (and rigorously conserved in Heff) polyad numbers due to a frequency ratio parity , inversion

Centrifugal distortion, rotational vibrational ℓ-doubling terms anharmonic Coriolis resonance interaction operators

IAO Tomsk global model (JQSRT2016) 24991 measured line positions from the literature up to 10000 cm-1 494 bands 144 diagonal parameters and 105 resonance interaction parameters RMS of about 4×10-3 cm-1 Effective Dipole Moment fitted for intensity modeling Similar to that developed at ULB but with less parameters: 18415 lines up to 8900 cm-1 / 396 parameters in JMS2011

Fig. 4

Band by band analysis

Fig. 9

{P, e/f, u/g, i} {V1, V2, V3, V4, V5, l4, l5}

CRDS MolPhys2014 JQSRT2013 FTS JQSRT2015 JQSRT2017 FTS JQSRT2016

Predictive capabilities

JQSRT in press doi10.1016/j.jqsrt.2017.01.036 10973 lines of 146 bands of 12C2H2 and 29 bands of 12C13CH2. Many hot bands 869 12C2H2. lines of 14 bands in HITRAN Smallest intensities on the order of 10-29 cm/molecule, about three orders of magnitude smaller than the HITRAN intensity cut off. Line profile parameters are added to the line list which is provided in HITRAN format.

variational line lists?

Merci! 25