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	hartrees
Energy at 0K	-77.338202
Energy at 298.15K	-77.338258
HF Energy	-77.338202
Nuclear repulsion energy	24.792401

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	3552	3428	0.00	63.77	0.23	0.38
2	Σ_g	2066	1994	0.00	53.80	0.22	0.35
3	Σ_u	3450	3330	82.80	0.00	0.00	0.00
4	Π_g	545	526	0.00	1.13	0.75	0.86
4	Π_g	545	526	0.00	1.13	0.75	0.86
5	Π_u	801	773	84.43	0.00	0.00	0.00
5	Π_u	801	773	84.43	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.601
C2	0.000	0.000	-0.601
H3	0.000	0.000	1.664
H4	0.000	0.000	-1.664

	C1	C2	H3	H4
C1		1.2014	1.0631	2.2646
C2	1.2014		2.2646	1.0631
H3	1.0631	2.2646		3.3277
H4	2.2646	1.0631	3.3277

Number	Element	Mulliken
1	C	-0.225
2	C	-0.225
3	H	0.225
4	H	0.225

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: TPSSh/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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<r²>	16.671
(<r²>)^1/2	4.083

All results from a given calculation for C2H2 (Acetylene)

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

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)