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

Table 1

Vibrational harmonic, 𝜔, and anharmonic, 𝜈, wavenumbers (cm⁻¹), infrared intensities, 𝐼_IR (km/mol), and Raman activities 𝐴_Raman (Å⁴/amu) of C₄H₄Te.

		Description^a	Calc.^b				Exp.^c
			𝐼IR	𝐴Raman	𝜔	𝜈	𝜈
A1	1	𝜈C–H	3	317	3237	3089	3084 (3106)
	2	𝜈C–H	12	259	3191	3052	3045 (3064)
	3	𝜈C=C + 𝜈C–C + 𝛿C–H	25	54	1465	1430	1432
	4	𝜈ring + 𝛿C–H	12	3	1341	1311	1316
	5	𝛿C–H	2	5	1103	1083	1079
	6	Ring breathing + 𝛿C–H	1	22	1010	986	984
	7	𝛿ring	18	22	702	692	687
	8	𝛿C–Te–C	0	9	385	380	380
A2	9	𝛾C–H	0	1	911	894	912
	10	𝛾C–H	0	0	684	663	690
	11	𝜏ring	0	0	512	503	507
B1	12	𝜈C–H	3	2	3234	3085	3084
	13	𝜈C–H	4	118	3176	3037	3030 (3047)
	14	𝜈C=C + 𝛿C–H	3	0	1548	1516	1516
	15	𝛿C–H	31	3	1255	1220	1246
	16	𝛿C–H	0	4	1099	1077	1079
	17	𝛿ring	3	0	805	794	797
	18	𝜈C–Te	2	8	557	547	552
B2	19	𝛾C–H	0	0	876	859	884
	20	𝛾C–H	132	0	683	667	674
	21	𝜏ring	5	0	358	355	354
		rms deviation^d			66	11
		rms deviation^e			144	6
		rms deviation^f			21	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]. The values in parentheses refer to the gas phase [11].
^dAll vibrational modes.
^e𝜈C–H modes.
^fAll vibrational modes excluding 𝜈C–H modes.