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	hartrees
Energy at 0K	-77.242270
Energy at 298.15K	-77.242442
HF Energy	-76.854292
Nuclear repulsion energy	24.756089

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	3557	3402	0.00	67.20	0.20	0.33
2	Σ_g	1993	1906	0.00	87.36	0.06	0.11
3	Σ_u	3468	3317	95.61	0.00	0.25	0.40
4	Π_g	661	632	0.00	2.15	0.75	0.86
4	Π_g	661	632	0.00	2.15	0.75	0.86
5	Π_u	768	734	88.91	0.00	0.65	0.79
5	Π_u	768	734	88.91	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.603
C2	0.000	0.000	-0.603
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.2060	1.0588	2.2649
C2	1.2060		2.2649	1.0588
H3	1.0588	2.2649		3.3237
H4	2.2649	1.0588	3.3237

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2=FULL/aug-cc-pVQZ

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/aug-cc-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)