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	hartrees
Energy at 0K	-77.181343
Energy at 298.15K	-77.180254
HF Energy	-76.846966
Nuclear repulsion energy	24.632688

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3534	3415
2	Σ_g	1976	1909
3	Σ_u	3444	3328
4	Π_g	90	87
4	Π_g	88	85
5	Π_u	720	696
5	Π_u	720	696

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	1.670
H4	0.000	0.000	-1.670

	C1	C2	H3	H4
C1		1.2127	1.0632	2.2759
C2	1.2127		2.2759	1.0632
H3	1.0632	2.2759		3.3392
H4	2.2759	1.0632	3.3392

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: MP4=FULL/TZVP

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: MP4=FULL/TZVP

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)