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	hartrees
Energy at 0K	-77.312923
Energy at 298.15K	-77.313018
HF Energy	-77.312923
Nuclear repulsion energy	24.739305

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	3463	3463	0.00	55.90	0.29	0.45
2	Σ_g	2015	2015	0.00	121.82	0.06	0.10
3	Σ_u	3369	3369	74.83	0.00	0.00	0.00
4	Π_g	607	607	0.00	3.00	0.75	0.86
4	Π_g	607	607	0.00	3.00	0.75	0.86
5	Π_u	742	742	94.92	0.00	0.00	0.00
5	Π_u	742	742	94.92	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.602
C2	0.000	0.000	-0.602
H3	0.000	0.000	1.668
H4	0.000	0.000	-1.668

	C1	C2	H3	H4
C1		1.2039	1.0657	2.2696
C2	1.2039		2.2696	1.0657
H3	1.0657	2.2696		3.3353
H4	2.2696	1.0657	3.3353

Number	Element	Mulliken
1	C	-0.599
2	C	-0.599
3	H	0.599
4	H	0.599

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B97D3/aug-cc-pVQZ

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>	17.097
(<r²>)^1/2	4.135

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B97D3/aug-cc-pVQZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)