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	hartrees
Energy at 0K	-76.252623
Energy at 298.15K	-76.252679
HF Energy	-76.252623
Nuclear repulsion energy	24.486560

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3678	3361	0.00
2	Σ_g	2170	1983	0.00
3	Σ_u	3537	3232	215.87
4	Π_g	658	601	0.00
4	Π_g	658	601	0.00
5	Π_u	799	730	36.77
5	Π_u	799	730	36.77

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	1.693
H4	0.000	0.000	-1.693

	C1	C2	H3	H4
C1		1.2115	1.0869	2.2984
C2	1.2115		2.2984	1.0869
H3	1.0869	2.2984		3.3853
H4	2.2984	1.0869	3.3853

Number	Element	Mulliken
1	C	-0.123
2	C	-0.123
3	H	0.123
4	H	0.123

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: PBEPBEultrafine/STO-3G

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>	16.520
(<r²>)^1/2	4.064

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: PBEPBEultrafine/STO-3G

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)