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	hartrees
Energy at 0K	-77.292947
Energy at 298.15K	-77.293091
HF Energy	-77.189396
Nuclear repulsion energy	24.793209

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	3531	3531	0.00	59.80	0.22	0.37
2	Σ_g	2029	2029	0.00	72.22	0.13	0.23
3	Σ_u	3439	3439	90.98	0.00	0.00	0.00
4	Π_g	637	637	0.00	4.22	0.75	0.86
4	Π_g	637	637	0.00	4.22	0.75	0.86
5	Π_u	766	766	100.71	0.00	0.00	0.00
5	Π_u	766	766	100.71	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.601
C2	0.000	0.000	-0.601
H3	0.000	0.000	1.662
H4	0.000	0.000	-1.662

	C1	C2	H3	H4
C1		1.2024	1.0609	2.2634
C2	1.2024		2.2634	1.0609
H3	1.0609	2.2634		3.3243
H4	2.2634	1.0609	3.3243

Number	Element	Mulliken
1	C	-0.223
2	C	-0.223
3	H	0.223
4	H	0.223

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: B2PLYP/Def2TZVPP

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>	17.049
(<r²>)^1/2	4.129

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: B2PLYP/Def2TZVPP

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)