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	hartrees
Energy at 0K	-77.159196
Energy at 298.15K	-77.159282
HF Energy	-76.848424
Nuclear repulsion energy	24.659294

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	3540	3361	0.00	63.73	0.25	0.40
2	Σ_g	1975	1875	0.00	50.75	0.16	0.28
3	Σ_u	3444	3271	96.07	0.00	0.00	0.00
4	Π_g	590	560	0.00	2.80	0.75	0.86
4	Π_g	590	560	0.00	2.80	0.75	0.86
5	Π_u	754	716	89.40	0.00	0.00	0.00
5	Π_u	754	716	89.40	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.606
C2	0.000	0.000	-0.606
H3	0.000	0.000	1.667
H4	0.000	0.000	-1.667

	C1	C2	H3	H4
C1		1.2114	1.0617	2.2731
C2	1.2114		2.2731	1.0617
H3	1.0617	2.2731		3.3348
H4	2.2731	1.0617	3.3348

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/cc-pVTZ

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/cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)