1. 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

2. 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…

3. VCH
cm-1
3 9640
2 6556
1 3281
23813 cm-1
9640 cm-1
6556 cm-1
3282 cm-1
Hall PhD thesis 1984

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

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

7. 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

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

9. IAO Tomsk global model (JQSRT2016)
24991 measured line positions from the literature up to 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

10. Fig. 4

11. Band by band analysis

12. Fig. 9

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

15. CRDS
MolPhys2014
JQSRT2013
FTS
JQSRT2015
JQSRT2017
FTS
JQSRT2016

16. Predictive capabilities

23. 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 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.

24. variational line lists?

25. Merci! 25