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	hartrees
Energy at 0K	-77.091458
Energy at 298.15K	-77.091344
HF Energy	-76.819667
Nuclear repulsion energy	24.578837

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	3593	3357	0.00	71.38	0.22	0.36
2	Σ_g	2003	1872	0.00	31.76	0.25	0.40
3	Σ_u	3502	3273	87.36	0.00	0.00	0.00
4	Π_g	458	428	0.00	0.75	0.75	0.86
4	Π_g	458	428	0.00	0.75	0.75	0.86
5	Π_u	755	706	80.47	0.00	0.00	0.00
5	Π_u	755	706	80.47	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.670
H4	0.000	0.000	-1.670

	C1	C2	H3	H4
C1		1.2171	1.0617	2.2787
C2	1.2171		2.2787	1.0617
H3	1.0617	2.2787		3.3404
H4	2.2787	1.0617	3.3404

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/6-31G**

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=FULL/6-31G**

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)