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	hartrees
Energy at 0K	-77.124751
Energy at 298.15K	-77.124729
HF Energy	-76.827136
Nuclear repulsion energy	24.658684

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	3591	3391	0.00	63.32	0.23	0.37
2	Σ_g	1993	1882	0.00	35.65	0.21	0.35
3	Σ_u	3500	3306	106.18	0.00	0.00	0.00
4	Π_g	503	475	0.00	0.66	0.75	0.86
4	Π_g	503	475	0.00	0.66	0.75	0.86
5	Π_u	777	734	81.03	0.00	0.00	0.00
5	Π_u	777	734	81.03	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.606
C2	0.000	0.000	-0.606
H3	0.000	0.000	1.667
H4	0.000	0.000	-1.667

	C1	C2	H3	H4
C1		1.2118	1.0609	2.2727
C2	1.2118		2.2727	1.0609
H3	1.0609	2.2727		3.3337
H4	2.2727	1.0609	3.3337

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/6-31G(2df,p)

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: MP2/6-31G(2df,p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)