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	hartrees
Energy at 0K	-153.074208
Energy at 298.15K
HF Energy	-152.504854
Nuclear repulsion energy	75.561020

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	Σ_g	3474	3394
2	Σ_g	2208	2157
3	Σ_g	897	876
4	Σ_u	3475	3395
5	Σ_u	2024	1978
6	Π_g	581	567
6	Π_g	581	567
7	Π_g	112i	109i
7	Π_g	112i	109i
8	Π_u	415	406
8	Π_u	415	406
9	Π_u	209	205
9	Π_u	209	205

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.695
C2	0.000	0.000	-0.695
C3	0.000	0.000	1.935
C4	0.000	0.000	-1.935
H5	0.000	0.000	3.012
H6	0.000	0.000	-3.012

	C1	C2	C3	C4	H5	H6
C1		1.3907	1.2395	2.6302	2.3170	3.7077
C2	1.3907		2.6302	1.2395	3.7077	2.3170
C3	1.2395	2.6302		3.8698	1.0775	4.9473
C4	2.6302	1.2395	3.8698		4.9473	1.0775
H5	2.3170	3.7077	1.0775	4.9473		6.0248
H6	3.7077	2.3170	4.9473	1.0775	6.0248

atom1	atom2	atom3	angle		atom1	atom2	atom3	angle
C1	C2	C4	180.000		C1	C3	H5	180.000
C2	C1	C3	180.000		C2	C4	H6	180.000

All results from a given calculation for C₄H₂ (Diacetylene)

using model chemistry: MP4/aug-cc-pVDZ

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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All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: MP4/aug-cc-pVDZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)