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	hartrees
Energy at 0K	-77.363187
Energy at 298.15K	-77.363347
HF Energy	-77.363187
Nuclear repulsion energy	24.827774

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	3513	3391	0.00	54.73	0.30	0.46
2	Σ_g	2056	1984	0.00	118.34	0.06	0.11
3	Σ_u	3409	3290	84.65	0.00	0.00	0.00
4	Π_g	640	617	0.00	3.15	0.75	0.86
4	Π_g	640	617	0.00	3.15	0.75	0.86
5	Π_u	777	750	98.78	0.00	0.00	0.00
5	Π_u	777	750	98.78	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.599
C2	0.000	0.000	-0.599
H3	0.000	0.000	1.663
H4	0.000	0.000	-1.663

	C1	C2	H3	H4
C1		1.1990	1.0632	2.2622
C2	1.1990		2.2622	1.0632
H3	1.0632	2.2622		3.3254
H4	2.2622	1.0632	3.3254

Number	Element	Mulliken
1	C	-0.313
2	C	-0.313
3	H	0.313
4	H	0.313

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: TPSSh/aug-cc-pVTZ

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>	16.986
(<r²>)^1/2	4.121

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: TPSSh/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)