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	hartrees
Energy at 0K	-12.427697
Energy at 298.15K	-12.427825
HF Energy	-12.427697
Nuclear repulsion energy	12.730636

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3532	3381	0.00
2	Σ_g	2067	1979	0.00
3	Σ_u	3409	3263	91.69
4	Π_g	600	575	0.00
4	Π_g	600	575	0.00
5	Π_u	820	785	131.20
5	Π_u	820	785	131.20

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.621
C2	0.000	0.000	-0.621
H3	0.000	0.000	1.697
H4	0.000	0.000	-1.697

	C1	C2	H3	H4
C1		1.2425	1.0760	2.3185
C2	1.2425		2.3185	1.0760
H3	1.0760	2.3185		3.3945
H4	2.3185	1.0760	3.3945

Number	Element	Mulliken
1	C	-0.356
2	C	-0.356
3	H	0.356
4	H	0.356

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3PW91/CEP-31G*

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>	15.765
(<r²>)^1/2	3.971

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3PW91/CEP-31G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)