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	hartrees
Energy at 0K	-153.416445
Energy at 298.15K	-153.416114
HF Energy	-153.416445
Nuclear repulsion energy	76.997189

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3492	3319	0.00
2	Σ_g	2368	2251	0.00
3	Σ_g	927	881	0.00
4	Σ_u	3493	3320	192.36
5	Σ_u	2175	2067	0.02
6	Π_g	811	770	0.00
6	Π_g	811	770	0.00
7	Π_g	660	627	0.00
7	Π_g	660	627	0.00
8	Π_u	709	674	96.35
8	Π_u	709	674	96.35
9	Π_u	275	262	6.87
9	Π_u	275	262	6.87

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	1.897
C4	0.000	0.000	-1.897
H5	0.000	0.000	2.964
H6	0.000	0.000	-2.964

	C1	C2	C3	C4	H5	H6
C1		1.3805	1.2069	2.5874	2.2733	3.6538
C2	1.3805		2.5874	1.2069	3.6538	2.2733
C3	1.2069	2.5874		3.7943	1.0664	4.8607
C4	2.5874	1.2069	3.7943		4.8607	1.0664
H5	2.2733	3.6538	1.0664	4.8607		5.9270
H6	3.6538	2.2733	4.8607	1.0664	5.9270

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: M06-2X/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	0.704
2	C	0.704
3	C	-0.940
4	C	-0.940
5	H	0.236
6	H	0.236

<r²>	78.692
(<r²>)^1/2	8.871

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: M06-2X/6-31G**

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)