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	hartrees
Energy at 0K	-12.312318
Energy at 298.15K	-12.312006
HF Energy	-12.061088
Nuclear repulsion energy	12.880785

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	3520	3354	0.00	69.36	0.23	0.38
2	Σ_g	1946	1854	0.00	45.91	0.18	0.31
3	Σ_u	3434	3272	77.50	0.00	0.00	0.00
4	Π_g	350	334	0.00	4.73	0.75	0.86
4	Π_g	350	334	0.00	4.73	0.75	0.86
5	Π_u	769	732	115.63	0.00	0.00	0.00
5	Π_u	769	732	115.63	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.612
C2	0.000	0.000	-0.612
H3	0.000	0.000	1.681
H4	0.000	0.000	-1.681

	C1	C2	H3	H4
C1		1.2240	1.0691	2.2931
C2	1.2240		2.2931	1.0691
H3	1.0691	2.2931		3.3622
H4	2.2931	1.0691	3.3622

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/CEP-121G*

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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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: MP2/CEP-121G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)