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	hartrees
Energy at 0K	-77.094414
Energy at 298.15K	-77.094240
HF Energy	-76.825630
Nuclear repulsion energy	24.291939

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	3518	3518	0.00	73.62	0.20	0.34
2	Σ_g	1946	1946	0.00	90.17	0.06	0.11
3	Σ_u	3427	3427	94.80	0.00	0.00	0.00
4	Π_g	432	432	0.00	2.20	0.75	0.86
4	Π_g	432	432	0.00	2.20	0.75	0.86
5	Π_u	720	720	93.07	0.00	0.00	0.00
5	Π_u	720	720	93.07	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.616
C2	0.000	0.000	-0.616
H3	0.000	0.000	1.690
H4	0.000	0.000	-1.690

	C1	C2	H3	H4
C1		1.2316	1.0740	2.3056
C2	1.2316		2.3056	1.0740
H3	1.0740	2.3056		3.3796
H4	2.3056	1.0740	3.3796

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP2/daug-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/daug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)