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	hartrees
Energy at 0K	-76.601132
Energy at 298.15K	-76.601023
HF Energy	-76.392979
Nuclear repulsion energy	24.471414

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3485	3485
2	Σ_g	1974	1974
3	Σ_u	3384	3384
4	Π_g	476	476
4	Π_g	476	476
5	Π_u	725	725
5	Π_u	725	725

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		1.2216	1.0683	2.2900
C2	1.2216		2.2900	1.0683
H3	1.0683	2.2900		3.3583
H4	2.2900	1.0683	3.3583

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP4=FULL/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=FULL/3-21G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)