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	hartrees
Energy at 0K	-153.432022
Energy at 298.15K	-153.431246
HF Energy	-153.432022
Nuclear repulsion energy	76.542948

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3415	3389	0.00
2	Σ_g	2215	2198	0.00
3	Σ_g	910	903	0.00
4	Σ_u	3418	3392	170.84
5	Σ_u	2049	2033	1.48
6	Π_g	688	683	0.00
6	Π_g	688	683	0.00
7	Π_g	560	555	0.00
7	Π_g	560	555	0.00
8	Π_u	526	522	90.34
8	Π_u	526	522	90.34
9	Π_u	267	265	3.51
9	Π_u	267	265	3.51

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	1.909
C4	0.000	0.000	-1.909
H5	0.000	0.000	2.980
H6	0.000	0.000	-2.980

	C1	C2	C3	C4	H5	H6
C1		1.3674	1.2249	2.5923	2.2959	3.6633
C2	1.3674		2.5923	1.2249	3.6633	2.2959
C3	1.2249	2.5923		3.8171	1.0710	4.8881
C4	2.5923	1.2249	3.8171		4.8881	1.0710
H5	2.2959	3.6633	1.0710	4.8881		5.9592
H6	3.6633	2.2959	4.8881	1.0710	5.9592

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: BLYP/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	0.715
2	C	0.715
3	C	-0.875
4	C	-0.875
5	H	0.160
6	H	0.160

<r²>	79.381
(<r²>)^1/2	8.910

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: BLYP/6-31G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)