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	hartrees
Energy at 0K	-153.431269
Energy at 298.15K	-153.430384
HF Energy	-153.431269
Nuclear repulsion energy	77.099191

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3416	3372	0.00
2	Σ_g	2211	2182	0.00
3	Σ_g	908	896	0.00
4	Σ_u	3419	3375	165.51
5	Σ_u	2047	2020	7.42
6	Π_g	609	601	0.00
6	Π_g	609	601	0.00
7	Π_g	526	519	0.00
7	Π_g	526	519	0.00
8	Π_u	608	600	85.21
8	Π_u	608	600	85.21
9	Π_u	228	225	7.84
9	Π_u	228	225	7.84

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.680
C2	0.000	0.000	-0.680
C3	0.000	0.000	1.894
C4	0.000	0.000	-1.894
H5	0.000	0.000	2.960
H6	0.000	0.000	-2.960

	C1	C2	C3	C4	H5	H6
C1		1.3598	1.2144	2.5742	2.2801	3.6399
C2	1.3598		2.5742	1.2144	3.6399	2.2801
C3	1.2144	2.5742		3.7886	1.0658	4.8543
C4	2.5742	1.2144	3.7886		4.8543	1.0658
H5	2.2801	3.6399	1.0658	4.8543		5.9201
H6	3.6399	2.2801	4.8543	1.0658	5.9201

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: B97D3/6-311+G(3df,2p)

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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Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
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Number	Element	Mulliken
1	C	0.059
2	C	0.059
3	C	-0.266
4	C	-0.266
5	H	0.206
6	H	0.206

<r²>	78.966
(<r²>)^1/2	8.886

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B97D3/6-311+G(3df,2p)

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)