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	hartrees
Energy at 0K	-153.493276
Energy at 298.15K	-153.492620
HF Energy	-153.493276
Nuclear repulsion energy	76.700276

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3478	3374	0.00
2	Σ_g	2290	2221	0.00
3	Σ_g	922	895	0.00
4	Σ_u	3480	3375	199.02
5	Σ_u	2115	2052	1.20
6	Π_g	666	646	0.00
6	Π_g	666	646	0.00
7	Π_g	579	562	0.00
7	Π_g	579	562	0.00
8	Π_u	652	632	82.32
8	Π_u	652	632	82.32
9	Π_u	246	238	5.75
9	Π_u	246	238	5.75

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.686
C2	0.000	0.000	-0.686
C3	0.000	0.000	1.904
C4	0.000	0.000	-1.904
H5	0.000	0.000	2.976
H6	0.000	0.000	-2.976

	C1	C2	C3	C4	H5	H6
C1		1.3726	1.2176	2.5903	2.2900	3.6626
C2	1.3726		2.5903	1.2176	3.6626	2.2900
C3	1.2176	2.5903		3.8079	1.0723	4.8802
C4	2.5903	1.2176	3.8079		4.8802	1.0723
H5	2.2900	3.6626	1.0723	4.8802		5.9526
H6	3.6626	2.2900	4.8802	1.0723	5.9526

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: B3LYP/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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Number	Element	Mulliken
1	C	0.664
2	C	0.664
3	C	-0.648
4	C	-0.648
5	H	-0.016
6	H	-0.016

<r²>	79.394
(<r²>)^1/2	8.910

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B3LYP/cc-pVDZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)