Anharmonic Spectroscopic Investigation of Tellurophene and Its Perdeuterated Isotopomer: Application of Second-Order Perturbation Theory

Table 2

Vibrational harmonic, 𝜔, and anharmonic, 𝜈, frequencies (cm⁻¹), infrared intensities, 𝐼_IR (km/mol), and Raman activities 𝐴_Raman (Å⁴/amu) of C₄D₄Te.

		Description^a	Calc.^b				Exp.^c
			𝐼IR	𝐴Raman	𝜔	𝜈	𝜈
A1	1	𝜈C–D	2	143	2400	2294	2308
	2	𝜈C–D	3	104	2355	2270	2262
	3	𝜈C=C + 𝜈C–C + 𝛿C–D	31	57	1443	1409	1405
	4	𝜈ring + 𝛿C–D	11	7	1208	1169	1180
	5	𝛿C–D	2	23	839	828	824
	6	Ring breathing + 𝛿C–D	0	10	782	770	768
	7	𝛿ring	14	12	640	632	630
	8	𝛿C–Te–C	0	9	374	371	370
A2	9	𝛾C–D	0	1	753	742	741
	10	𝛾C–D	0	0	533	520	548
	11	𝜏ring	0	0	438	432	437
B1	12	𝜈C–D	1	4	2395	2313	2308
	13	𝜈C–D	1	55	2339	2249	2240
	14	𝜈C=C + 𝛿C–D	7	0	1493	1458	1455
	15	𝛿C–D	12	2	1002	986	995
	16	𝛿C–D	2	4	853	840	811
	17	𝛿ring	1	0	706	697	704
	18	𝜈C–Te	3	7	524	517	522
B2	19	𝛾C–D	0	0	683	673	696
	20	𝛾C–D	77	0	506	497	502
	21	𝜏ring	3	0	329	325	326
		rms deviation^d			43	12
		rms deviation^e			91	10
		rms deviation^f			18	12

 ^a𝜈: stretching; 𝛿: in-plane bending; 𝜏: torsion; 𝛾: out-of-plane bending.
^bCalculations were carried out in vacuum at the B3LYP/LANL2DZ(d,p) level.
^cLiquid phase [12].
^dAll vibrational modes.
^e𝜈C–H modes.
^fAll vibrational modes excluding 𝜈C–H modes.