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	hartrees
Energy at 0K	-76.598093
Energy at 298.15K	-76.597989
HF Energy	-76.392957
Nuclear repulsion energy	24.469189

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3485	3379
2	Σ_g	1974	1914
3	Σ_u	3384	3282
4	Π_g	477	462
4	Π_g	477	462
5	Π_u	725	703
5	Π_u	725	703

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.611
C2	0.000	0.000	-0.611
H3	0.000	0.000	1.679
H4	0.000	0.000	-1.679

	C1	C2	H3	H4
C1		1.2218	1.0684	2.2902
C2	1.2218		2.2902	1.0684
H3	1.0684	2.2902		3.3586
H4	2.2902	1.0684	3.3586

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP4/3-21G

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: MP4/3-21G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)