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	hartrees
Energy at 0K	-153.205961
Energy at 298.15K
HF Energy	-152.550335
Nuclear repulsion energy	76.711775

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.690
C2	0.000	0.000	-0.690
C3	0.000	0.000	1.905
C4	0.000	0.000	-1.905
H5	0.000	0.000	2.970
H6	0.000	0.000	-2.970

	C1	C2	C3	C4	H5	H6
C1		1.3790	1.2159	2.5949	2.2803	3.6593
C2	1.3790		2.5949	1.2159	3.6593	2.2803
C3	1.2159	2.5949		3.8108	1.0644	4.8752
C4	2.5949	1.2159	3.8108		4.8752	1.0644
H5	2.2803	3.6593	1.0644	4.8752		5.9396
H6	3.6593	2.2803	4.8752	1.0644	5.9396

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)/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)/aug-cc-pVTZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)