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	hartrees
Energy at 0K	-77.310919
Energy at 298.15K	-77.310988
HF Energy	-77.310919
Nuclear repulsion energy	24.650085

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	3545	3398	0.00	53.52	0.27	0.43
2	Σ_g	2080	1993	0.00	116.23	0.07	0.13
3	Σ_u	3439	3295	92.95	0.00	0.00	0.00
4	Π_g	582	558	0.00	3.44	0.75	0.86
4	Π_g	582	558	0.00	3.44	0.75	0.86
5	Π_u	742	711	101.78	0.00	0.00	0.00
5	Π_u	742	711	101.78	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.604
C2	0.000	0.000	-0.604
H3	0.000	0.000	1.674
H4	0.000	0.000	-1.674

	C1	C2	H3	H4
C1		1.2079	1.0704	2.2782
C2	1.2079		2.2782	1.0704
H3	1.0704	2.2782		3.3486
H4	2.2782	1.0704	3.3486

Number	Element	Mulliken
1	C	0.301
2	C	0.301
3	H	-0.301
4	H	-0.301

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: mPW1PW91/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>	17.136
(<r²>)^1/2	4.140

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: mPW1PW91/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)