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	hartrees
Energy at 0K	-76.998392
Energy at 298.15K	-76.998432
HF Energy	-76.794971
Nuclear repulsion energy	24.124183

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3454	3294
2	Σ_g	1913	1824
3	Σ_u	3360	3204
4	Π_g	602	574
4	Π_g	602	574
5	Π_u	699	666
5	Π_u	699	666

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.621
C2	0.000	0.000	-0.621
H3	0.000	0.000	1.698
H4	0.000	0.000	-1.698

	C1	C2	H3	H4
C1		1.2424	1.0766	2.3189
C2	1.2424		2.3189	1.0766
H3	1.0766	2.3189		3.3955
H4	2.3189	1.0766	3.3955

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: QCISD(T)/SDD

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: QCISD(T)/SDD

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)