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	hartrees
Energy at 0K	-77.302783
Energy at 298.15K	-77.302895
HF Energy	-77.302783
Nuclear repulsion energy	24.743426

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	3562	3389	0.00	61.59	0.20	0.33
2	Σ_g	2102	2000	0.00	52.39	0.25	0.41
3	Σ_u	3460	3292	88.79	0.00	0.00	0.00
4	Π_g	603	574	0.00	1.64	0.75	0.86
4	Π_g	603	574	0.00	1.64	0.75	0.86
5	Π_u	781	743	87.19	0.00	0.00	0.00
5	Π_u	781	743	87.19	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	1.667
H4	0.000	0.000	-1.667

	C1	C2	H3	H4
C1		1.2039	1.0651	2.2690
C2	1.2039		2.2690	1.0651
H3	1.0651	2.2690		3.3342
H4	2.2690	1.0651	3.3342

Number	Element	Mulliken
1	C	-0.189
2	C	-0.189
3	H	0.189
4	H	0.189

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>	16.707
(<r²>)^1/2	4.087

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)