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	hartrees
Energy at 0K	-77.284696
Energy at 298.15K	-77.284605
HF Energy	-77.284696
Nuclear repulsion energy	24.483984

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	3472	3472	0.00	60.44	0.27	0.43
2	Σ_g	2012	2012	0.00	116.96	0.07	0.13
3	Σ_u	3372	3372	74.15	0.00	0.00	0.00
4	Π_g	490	490	0.00	3.66	0.75	0.86
4	Π_g	490	490	0.00	3.66	0.75	0.86
5	Π_u	704	704	98.37	0.00	0.00	0.00
5	Π_u	704	704	98.37	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.683
H4	0.000	0.000	-1.683

	C1	C2	H3	H4
C1		1.2176	1.0744	2.2920
C2	1.2176		2.2920	1.0744
H3	1.0744	2.2920		3.3664
H4	2.2920	1.0744	3.3664

Number	Element	Mulliken
1	C	0.386
2	C	0.386
3	H	-0.386
4	H	-0.386

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B97D3/aug-cc-pVDZ

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>	17.332
(<r²>)^1/2	4.163

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B97D3/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)