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	hartrees
Energy at 0K	-12.277658
Energy at 298.15K	-12.277770
HF Energy	-12.038747
Nuclear repulsion energy	12.642858

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3535	3333	0.00
2	Σ_g	1941	1829	0.00
3	Σ_u	3430	3234	88.05
4	Π_g	594	560	0.00
4	Π_g	594	560	0.00
5	Π_u	809	762	130.92
5	Π_u	809	762	130.92

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.628
C2	0.000	0.000	-0.628
H3	0.000	0.000	1.704
H4	0.000	0.000	-1.704

	C1	C2	H3	H4
C1		1.2567	1.0757	2.3325
C2	1.2567		2.3325	1.0757
H3	1.0757	2.3325		3.4082
H4	2.3325	1.0757	3.4082

All results from a given calculation for C₂H₂ (Acetylene)

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

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)