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	hartrees
Energy at 0K	-77.092997
Energy at 298.15K	-77.092762
HF Energy	-76.825208
Nuclear repulsion energy	24.284530

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	3519	3375	0.00	74.07	0.20	0.34
2	Σ_g	1946	1866	0.00	83.25	0.08	0.14
3	Σ_u	3432	3291	93.32	0.00	0.00	0.00
4	Π_g	408	392	0.00	2.65	0.75	0.86
4	Π_g	408	392	0.00	2.65	0.75	0.86
5	Π_u	703	674	94.60	0.00	0.00	0.00
5	Π_u	703	674	94.60	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	1.691
H4	0.000	0.000	-1.691

	C1	C2	H3	H4
C1		1.2315	1.0752	2.3067
C2	1.2315		2.3067	1.0752
H3	1.0752	2.3067		3.3819
H4	2.3067	1.0752	3.3819

All results from a given calculation for C₂H₂ (Acetylene)

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

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)