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	hartrees
Energy at 0K	-77.076215
Energy at 298.15K	-77.075975
HF Energy	-76.815577
Nuclear repulsion energy	24.559807

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	3571	3364	0.00	69.65	0.23	0.37
2	Σ_g	2005	1889	0.00	31.72	0.25	0.40
3	Σ_u	3482	3281	84.91	0.00	0.00	0.00
4	Π_g	394	371	0.00	0.79	0.75	0.86
4	Π_g	394	371	0.00	0.79	0.75	0.86
5	Π_u	751	708	88.24	0.00	0.00	0.00
5	Π_u	751	708	88.24	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.608
C2	0.000	0.000	-0.608
H3	0.000	0.000	1.674
H4	0.000	0.000	-1.674

	C1	C2	H3	H4
C1		1.2164	1.0659	2.2822
C2	1.2164		2.2822	1.0659
H3	1.0659	2.2822		3.3481
H4	2.2822	1.0659	3.3481

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)