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	hartrees
Energy at 0K	-151.627269
Energy at 298.15K
HF Energy	-151.162884
Nuclear repulsion energy	62.828433

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	2196	2196
2	Σ_g	1101	1101
3	Σ_u	3156	3156
4	Π_g	326	326
4	Π_g	326	326
5	Π_u	184	184
5	Π_u	184	184

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.650
C2	0.000	0.000	-0.650
C3	0.000	0.000	1.973
C4	0.000	0.000	-1.973

	C1	C2	C3	C4
C1		1.2999	1.3226	2.6225
C2	1.2999		2.6225	1.3226
C3	1.3226	2.6225		3.9451
C4	2.6225	1.3226	3.9451

Number	Element	Mulliken
1	C	0.514
2	C	0.514
3	C	-0.514
4	C	-0.514

All results from a given calculation for C₄ (Carbon tetramer)

using model chemistry: ROMP2/6-31+G**

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>	67.954
(<r²>)^1/2	8.243

All results from a given calculation for C4 (Carbon tetramer)

using model chemistry: ROMP2/6-31+G**

States and conformations

All results from a given calculation for C₄ (Carbon tetramer)