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	hartrees
Energy at 0K	-77.362343
Energy at 298.15K	-77.362494
HF Energy	-77.362343
Nuclear repulsion energy	24.830189

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	3514	3402	0.00	56.86	0.29	0.45
2	Σ_g	2058	1993	0.00	73.65	0.16	0.28
3	Σ_u	3410	3302	84.01	0.00	0.00	0.00
4	Π_g	632	612	0.00	3.27	0.75	0.86
4	Π_g	632	612	0.00	3.27	0.75	0.86
5	Π_u	776	752	96.59	0.00	0.00	0.00
5	Π_u	776	752	96.59	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		1.1988	1.0633	2.2620
C2	1.1988		2.2620	1.0633
H3	1.0633	2.2620		3.3253
H4	2.2620	1.0633	3.3253

Number	Element	Mulliken
1	C	-0.124
2	C	-0.124
3	H	0.124
4	H	0.124

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: TPSSh/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>	16.897
(<r²>)^1/2	4.111

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: TPSSh/cc-pVTZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)