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	hartrees
Energy at 0K	-153.408769
Energy at 298.15K	-153.408213
HF Energy	-153.408769
Nuclear repulsion energy	77.147737

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3518	3339	0.00
2	Σ_g	2332	2214	0.00
3	Σ_g	931	884	0.00
4	Σ_u	3520	3341	163.38
5	Σ_u	2150	2041	0.51
6	Π_g	717	681	0.00
6	Π_g	717	681	0.00
7	Π_g	625	593	0.00
7	Π_g	625	593	0.00
8	Π_u	624	592	96.88
8	Π_u	624	592	96.88
9	Π_u	267	254	5.66
9	Π_u	267	254	5.66

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.684
C2	0.000	0.000	-0.684
C3	0.000	0.000	1.893
C4	0.000	0.000	-1.893
H5	0.000	0.000	2.959
H6	0.000	0.000	-2.959

	C1	C2	C3	C4	H5	H6
C1		1.3678	1.2092	2.5770	2.2746	3.6424
C2	1.3678		2.5770	1.2092	3.6424	2.2746
C3	1.2092	2.5770		3.7861	1.0654	4.8516
C4	2.5770	1.2092	3.7861		4.8516	1.0654
H5	2.2746	3.6424	1.0654	4.8516		5.9170
H6	3.6424	2.2746	4.8516	1.0654	5.9170

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: B1B95/6-31G*

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	0.657
2	C	0.657
3	C	-0.913
4	C	-0.913
5	H	0.256
6	H	0.256

<r²>	78.281
(<r²>)^1/2	8.848

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B1B95/6-31G*

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)