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	hartrees
Energy at 0K	-77.185733
Energy at 298.15K	-77.182046
Nuclear repulsion energy	25.069716

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	Σ_g	3721	3506	0.00	51.68	0.21	0.35
2	Σ_g	2247	2117	0.00	61.16	0.26	0.41
3	Σ_u	3609	3400	81.31	0.00	0.00	0.00
4	Π_g	793	747	0.00	3.62	0.75	0.86
4	Π_g	793	747	0.00	3.62	0.75	0.86
5	Π_u	881	831	100.41	0.00	0.00	0.00
5	Π_u	881	831	100.41	0.00	0.00	0.00

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.608
C2	0.000	0.000	-0.608
H3	0.000	0.000	1.674
H4	0.000	0.000	-1.674

	C1	C2	H3	H4
C1		1.2164	1.0659	2.2822
C2	1.2164		2.2822	1.0659
H3	1.0659	2.2822		3.3481
H4	2.2822	1.0659	3.3481

All results from a given calculation for C₂H₂ (Acetylene)

using model chemistry: G2

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
	Home All data for one species Geometry Experimental Experimental Geometries Same bond/angle many molecules Internal Coordinates by type Bond angles Calculated Calculated geometry Rotational constant Moments of inertia Products of moments of inertia BSE Bond lengths Show me a calculated geometry Comparisons Bonds, angles Rotational Constants Products of moments of inertia Point group Bad Calculations Bad moment of inertia Tutorials and Explanations Angle formulas Vibrations Experimental Vibrational frequencies Calculated Frequencies Scale factors Reactions Entropies Ions List Ions Energy Calculated Ionization Energy Compare Ionzation energy Electron Affinity Calculated Electron affinity Compare Electron affinity Proton Affinity Calculated Proton affinity Compare Proton affinity Ionization changes point group Experimental One molecule all properties One property a few molecules Enthalpy of formation Entropy Integrated Heat Capacity Heat Capacity Rotational Constants Vibrational Frequencies Dipole moment Ionization Energy Polarizability Quadrupole Point Groups Geometry Experimental Geometries Internal Coordinates by type Bond angles Rotational Constants Point Groups Diatomic bond lengths Vibrations Vibrational frequencies Diatomic Triatomics Energy Atomization Energy Internal Rotation Electrostatics Dipole Quadrupole Polarizability Reference Data Reference states Spin Splittings Molecules with good enthalpy Enthalpy at 0 Kelvin Calculated Energy Optimized Energy Energy 298K Minimum conformation Hydrogen bonds H bond with counterpoise Reaction Reaction Energy 0K Reaction Energy 298K Internal Rotation Barriers to internal rotation Rotational barrier and dipole Rotational Barrier 2 molecules Orbital HOMO LUMO gap HOMO Orbital Energies Nuclear repulsion energy Correlation Full vs Frozen core energies Partial correlation energies Ion Calculated Ionization Energy Vertical ionization Energy Calculated Electron affinity Calculated Proton affinity Atom charge differences Excited State Singlet triplet gap Electronic state Transition state Basis Set Extrapolation BSE energy BSE Bond lengths Geometry Calculated geometry AIM bond orders One type of bond Rotation Rotational constant Products of moments of inertia Moments of inertia Inertial defects Second moments Point group State symmetry <r2> Sorted by r2 Z-matrix Bad Calculations Bad moment of inertia Bad Calculated Bond Lengths Bad point group Worst molecules Vibrations Frequencies Animated vibrations Anharmonic Zero point energy (ZPE) Scale Factors Scale factors Scale factor uncertainty Calculate a scale factor Why scale vibrations Set scaling factors Bad Calculations Bad Vib. 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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: G2

States and conformations

All results from a given calculation for C₂H₂ (Acetylene)