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	hartrees
Energy at 0K	-153.280098
Energy at 298.15K
HF Energy	-152.551512
Nuclear repulsion energy	77.054899

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.685
C2	0.000	0.000	-0.685
C3	0.000	0.000	1.897
C4	0.000	0.000	-1.897
H5	0.000	0.000	2.957
H6	0.000	0.000	-2.957

	C1	C2	C3	C4	H5	H6
C1		1.3707	1.2112	2.5819	2.2720	3.6427
C2	1.3707		2.5819	1.2112	3.6427	2.2720
C3	1.2112	2.5819		3.7931	1.0608	4.8539
C4	2.5819	1.2112	3.7931		4.8539	1.0608
H5	2.2720	3.6427	1.0608	4.8539		5.9147
H6	3.6427	2.2720	4.8539	1.0608	5.9147

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: QCISD(T)=FULL/aug-cc-pVTZ

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: QCISD(T)=FULL/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)