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	hartrees
Energy at 0K	-77.136383
Energy at 298.15K	-77.136464
HF Energy	-76.828417
Nuclear repulsion energy	24.829444

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3611	3611	0.00
2	Σ_g	2106	2106	0.00
3	Σ_u	3508	3508	98.34
4	Π_g	564	564	0.00
4	Π_g	564	564	0.00
5	Π_u	802	802	85.19
5	Π_u	802	802	85.19

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.600
C2	0.000	0.000	-0.600
H3	0.000	0.000	1.660
H4	0.000	0.000	-1.660

	C1	C2	H3	H4
C1		1.2003	1.0603	2.2606
C2	1.2003		2.2606	1.0603
H3	1.0603	2.2606		3.3209
H4	2.2606	1.0603	3.3209

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP3/6-31G(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: MP3/6-31G(2df,p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)