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	hartrees
Energy at 0K	-76.872541
Energy at 298.15K	-76.872671
HF Energy	-76.872541
Nuclear repulsion energy	24.590632

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	3465	3446	0.00	62.60	0.19	0.33
2	Σ_g	2028	2017	0.00	40.81	0.29	0.45
3	Σ_u	3358	3340	73.87	0.00	0.00	0.00
4	Π_g	632	629	0.00	1.54	0.75	0.86
4	Π_g	632	629	0.00	1.54	0.75	0.86
5	Π_u	757	753	92.89	0.00	0.00	0.00
5	Π_u	757	753	92.89	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.606
C2	0.000	0.000	-0.606
H3	0.000	0.000	1.675
H4	0.000	0.000	-1.675

	C1	C2	H3	H4
C1		1.2128	1.0687	2.2815
C2	1.2128		2.2815	1.0687
H3	1.0687	2.2815		3.3503
H4	2.2815	1.0687	3.3503

Number	Element	Mulliken
1	C	-0.217
2	C	-0.217
3	H	0.217
4	H	0.217

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: BLYP/3-21G

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>	16.984
(<r²>)^1/2	4.121

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: BLYP/3-21G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)