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	hartrees
Energy at 0K	-77.291386
Energy at 298.15K	-77.291600
HF Energy	-77.291386
Nuclear repulsion energy	24.522812

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3571	3392	0.00
2	Σ_g	2044	1941	0.00
3	Σ_u	3465	3291	84.73
4	Π_g	698	663	0.00
4	Π_g	698	663	0.00
5	Π_u	792	752	143.10
5	Π_u	792	752	143.10

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.609
C2	0.000	0.000	-0.609
H3	0.000	0.000	1.676
H4	0.000	0.000	-1.676

	C1	C2	H3	H4
C1		1.2188	1.0663	2.2851
C2	1.2188		2.2851	1.0663
H3	1.0663	2.2851		3.3513
H4	2.2851	1.0663	3.3513

Number	Element	Mulliken
1	C	-0.270
2	C	-0.270
3	H	0.270
4	H	0.270

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: mPW1PW91/SDD

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>	17.057
(<r²>)^1/2	4.130

All results from a given calculation for C2H2 (Acetylene)

using model chemistry: mPW1PW91/SDD

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)