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	hartrees
Energy at 0K	-77.335268
Energy at 298.15K	-77.335328
HF Energy	-77.335268
Nuclear repulsion energy	24.836056

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	3558	3433	0.00	59.67	0.23	0.37
2	Σ_g	2079	2006	0.00	52.28	0.22	0.36
3	Σ_u	3455	3334	90.73	0.00	0.00	0.00
4	Π_g	550	531	0.00	0.90	0.75	0.86
4	Π_g	550	531	0.00	0.90	0.75	0.86
5	Π_u	796	768	81.58	0.00	0.00	0.00
5	Π_u	796	768	81.58	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.599
C2	0.000	0.000	-0.599
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.1989	1.0622	2.2611
C2	1.1989		2.2611	1.0622
H3	1.0622	2.2611		3.3232
H4	2.2611	1.0622	3.3232

Number	Element	Mulliken
1	C	-0.207
2	C	-0.207
3	H	0.207
4	H	0.207

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B3LYPultrafine/6-31G(2df,p)

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>	16.667
(<r²>)^1/2	4.083

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B3LYPultrafine/6-31G(2df,p)

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)