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	hartrees
Energy at 0K	-153.424830
Energy at 298.15K	-153.424198
HF Energy	-153.424830
Nuclear repulsion energy	76.732779

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3490	3367	0.00
2	Σ_g	2301	2221	0.00
3	Σ_g	929	896	0.00
4	Σ_u	3491	3369	200.17
5	Σ_u	2119	2045	1.49
6	Π_g	676	652	0.00
6	Π_g	676	652	0.00
7	Π_g	581	561	0.00
7	Π_g	581	561	0.00
8	Π_u	663	640	83.77
8	Π_u	663	640	83.77
9	Π_u	245	236	6.68
9	Π_u	245	236	6.68

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	1.903
C4	0.000	0.000	-1.903
H5	0.000	0.000	2.976
H6	0.000	0.000	-2.976

	C1	C2	C3	C4	H5	H6
C1		1.3704	1.2178	2.5881	2.2905	3.6609
C2	1.3704		2.5881	1.2178	3.6609	2.2905
C3	1.2178	2.5881		3.8059	1.0728	4.8787
C4	2.5881	1.2178	3.8059		4.8787	1.0728
H5	2.2905	3.6609	1.0728	4.8787		5.9515
H6	3.6609	2.2905	4.8787	1.0728	5.9515

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: B3PW91/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	0.646
2	C	0.646
3	C	-0.656
4	C	-0.656
5	H	0.010
6	H	0.010

<r²>	79.221
(<r²>)^1/2	8.901

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B3PW91/cc-pVDZ

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)