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	hartrees
Energy at 0K	-77.082680
Energy at 298.15K	-77.082720
HF Energy	-76.822742
Nuclear repulsion energy	24.306904

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	3540	3372	0.00	72.75	0.23	0.38
2	Σ_g	1965	1872	0.00	37.09	0.24	0.39
3	Σ_u	3455	3291	99.02	0.00	0.00	0.00
4	Π_g	559	532	0.00	1.21	0.75	0.86
4	Π_g	559	532	0.00	1.21	0.75	0.86
5	Π_u	749	714	77.52	0.00	0.00	0.00
5	Π_u	749	714	77.52	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.615
C2	0.000	0.000	-0.615
H3	0.000	0.000	1.690
H4	0.000	0.000	-1.690

	C1	C2	H3	H4
C1		1.2298	1.0755	2.3052
C2	1.2298		2.3052	1.0755
H3	1.0755	2.3052		3.3807
H4	2.3052	1.0755	3.3807

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/cc-pVDZ

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/cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)