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	hartrees
Energy at 0K	-77.298942
Energy at 298.15K	-77.299022
HF Energy	-77.298942
Nuclear repulsion energy	24.743605

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	3568	3384	0.00	60.24	0.21	0.35
2	Σ_g	2104	1996	0.00	51.32	0.26	0.41
3	Σ_u	3465	3286	78.32	0.00	0.00	0.00
4	Π_g	581	550	0.00	1.89	0.75	0.86
4	Π_g	581	550	0.00	1.89	0.75	0.86
5	Π_u	783	743	88.86	0.00	0.00	0.00
5	Π_u	783	743	88.86	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		1.2034	1.0660	2.2694
C2	1.2034		2.2694	1.0660
H3	1.0660	2.2694		3.3355
H4	2.2694	1.0660	3.3355

Number	Element	Mulliken
1	C	-0.227
2	C	-0.227
3	H	0.227
4	H	0.227

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: mPW1PW91/6-31G*

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>	16.708
(<r²>)^1/2	4.088

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: mPW1PW91/6-31G*

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)