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	hartrees
Energy at 0K	-77.300334
Energy at 298.15K	-77.300434
HF Energy	-77.300334
Nuclear repulsion energy	24.810228

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3559	3422	0.00	58.44	0.23	0.37
2	Σ_g	2080	2000	0.00	53.11	0.21	0.35
3	Σ_u	3456	3322	91.63	0.00	0.00	0.00
4	Π_g	583	561	0.00	1.10	0.75	0.86
4	Π_g	583	561	0.00	1.10	0.75	0.86
5	Π_u	794	763	84.82	0.00	0.00	0.00
5	Π_u	794	763	84.82	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.600
C2	0.000	0.000	-0.600
H3	0.000	0.000	1.664
H4	0.000	0.000	-1.664

	C1	C2	H3	H4
C1		1.1999	1.0638	2.2637
C2	1.1999		2.2637	1.0638
H3	1.0638	2.2637		3.3276
H4	2.2637	1.0638	3.3276

Number	Element	Mulliken
1	C	-0.231
2	C	-0.231
3	H	0.231
4	H	0.231

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3PW91/6-31G(2df,p)

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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<r²>	16.652
(<r²>)^1/2	4.081

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3PW91/6-31G(2df,p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)