CCCBDB calculation results Page

Home
- All data for one species
- Geometry
  - Experimental
  - Calculated
  - Comparisons
  - 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
Calculated
- Energy
  - Optimized
  - Reaction
    - Reaction Energy 0K
    - Reaction Energy 298K
  - Internal Rotation
  - Orbital
  - Nuclear repulsion energy
  - Correlation
    - Full vs Frozen core energies
    - Partial correlation energies
  - Ion
  - Excited State
  - Basis Set Extrapolation
    - BSE energy
    - BSE Bond lengths
- Geometry
  - Calculated geometry
    - AIM bond orders
    - One type of bond
  - Rotation
  - Point group
  - State symmetry
  - <r2>
    - Sorted by r2
  - Z-matrix
  - Bad Calculations
- Vibrations
  - Frequencies
    - Animated vibrations
    - Anharmonic
  - Zero point energy (ZPE)
  - Scale Factors
  - Bad Calculations
- Electrostatics
  - Charges
  - Dipole
  - Quadrupole
  - Polarizability
  - Spin
    - Spin density
- Entropy and Heat Capacity
- Reaction
  - Reaction Energy 0K
  - Reaction Energy 298K
  - Isodesmic reactions
  - Transition State
- Lookup by property
  - By frequency
Comparisons
- Geometry
- Vibrations
- Energy
  - Reaction
  - Single point vs optimized
  - DFT grid size on energy
  - Semiempirical enthalpy
  - Internal rotation
  - Similar molecules
- Entropy
- Electrostatics
- Ion
Resources
- Info on Results
  - Calculations Done
  - Basis functions used
  - I/O files
- Glossary
- Conversion Forms
- Links
  - NIST Links
  - External links
- Thermochemistry
- Tutorials
  - Vibrations
    - Why scale vibrations
    - Zero-point energies
  - Entropy
    - Methyl rotor entropy
    - Entropy and conformations
  - Energy
  - Electrostatics
    - Dipole parts by point group
    - Quadrupoles
  - Geometry
    - Angle formulas
  - Cost
    - Cost Comparison
    - Timings Comparison
- Bad Calculations
  - Geometry
  - Vibrations
  - Low excited states
  - Oddities
    - NaCN Is not linear
FAQ Help
- Units
  - Choose Units
  - Explanations
- Credits
- Just show me
  - Show me a calculated geometry
- Summary
- Using
- List
  - Recent molecules
    - Choose a few
  - Molecules
  - Geometry
  - Vibrations
    - Big anharmonicity
  - Energy
    - Enthalpy at 0 Kelvin
  - Similar molecules
  - Ions, Dipoles, etc.
- Index of CCCBDB
- Feedback
  - Error form
  - Wants

	hartrees
Energy at 0K	-223.613373
Energy at 298.15K	-223.619363
HF Energy	-223.613373
Nuclear repulsion energy	165.926170

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	3179	3122	8.26
2	A₁	3003	2949	4.25
3	A₁	1668	1638	20.44
4	A₁	1359	1335	34.57
5	A₁	1328	1304	0.32
6	A₁	1217	1195	13.14
7	A₁	1027	1009	15.37
8	A₁	874	858	7.15
9	A₂	1126	1106	0.00
10	A₂	930	913	0.00
11	A₂	572	562	0.00
12	B₁	3044	2990	4.82
13	B₁	959	942	15.03
14	B₁	829	814	9.53
15	B₁	386	379	51.38
16	B₂	3163	3106	8.14
17	B₂	1720	1689	0.22
18	B₂	1266	1243	8.43
19	B₂	1195	1174	0.31
20	B₂	1062	1043	27.82
21	B₂	944	927	101.38

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	1.208
N2	0.000	0.997	0.284
N3	0.000	-0.997	0.284
C4	0.000	0.735	-0.951
C5	0.000	-0.735	-0.951
H6	-0.902	0.000	1.846
H7	0.902	0.000	1.846
H8	0.000	1.470	-1.755
H9	0.000	-1.470	-1.755

	C1	N2	N3	C4	C5	H6	H7	H8	H9
C1		1.3592	1.3592	2.2805	2.2805	1.1046	1.1046	3.3071	3.3071
N2	1.3592		1.9942	1.2627	2.1272	2.0605	2.0605	2.0930	3.2003
N3	1.3592	1.9942		2.1272	1.2627	2.0605	2.0605	3.2003	2.0930
C4	2.2805	1.2627	2.1272		1.4695	3.0289	3.0289	1.0891	2.3463
C5	2.2805	2.1272	1.2627	1.4695		3.0289	3.0289	2.3463	1.0891
H6	1.1046	2.0605	2.0605	3.0289	3.0289		1.8037	3.9920	3.9920
H7	1.1046	2.0605	2.0605	3.0289	3.0289	1.8037		3.9920	3.9920
H8	3.3071	2.0930	3.2003	1.0891	2.3463	3.9920	3.9920		2.9391
H9	3.3071	3.2003	2.0930	2.3463	1.0891	3.9920	3.9920	2.9391

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	N2	C4	120.822	C1	N3	C5	120.822
N2	C1	N3	94.377	N2	C1	H6	113.103
N2	C1	H7	113.103	N2	C4	C5	101.990
N2	C4	H8	125.580	N3	C1	H6	113.103
N3	C1	H7	113.103	N3	C5	C4	101.990
N3	C5	H9	125.580	C4	C5	H9	132.430
C5	C4	H8	132.430	H6	C1	H7	109.466

All results from a given calculation for C₃H₄N₂ (2H-Imidazole)

using model chemistry: LSDA/3-21G*

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. HF vs MP2 Bad vib. Calc. vs exp. Big anharmonicity Electrostatics Charges Mulliken CHELP Aim ESP Dipole Dipole Dipole angle Dipole calculation types Quadrupole Polarizability Spin Spin density Entropy and Heat Capacity Entropy Reaction entropy Heat Capacity Reaction Reaction Energy 0K Reaction Energy 298K Isodesmic reactions Transition State Transition state Transition state frequencies Transition state geometries IRC Lookup by property By frequency Comparisons Geometry Bonds, angles Bond, angle, or dihedral DFT grid size on point group DFT grid on bond length Core correlation - bond length Same bond/angle many molecules Isoelectronic diatomics Isoelectronic triatomic angles Average bond lengths Rotation Rotational Constants Products of moments of inertia Point group Vibrations Vibrations 2 calculations Frequency differences One frequency Zero point energy Intensity Intensity for one mode Vibrational intensities Reduced mass comparison Anharmonic Triatomic Scale factors Energy Reaction Reaction Energy 0K Reaction Energy 298K Atomization 0K Atomization 298K Single point vs optimized DFT grid size on energy Semiempirical enthalpy Internal rotation Similar molecules Conformation Sets of isomers Sets of tautomers Isomers Entropy Entropy Heat capacity Entropy of several molecules Integrated heat capacity Reaction entropy Electrostatics Dipole Polarizability Several molecules Quadrupole Ion Compare Ionzation energy Koopman ionization energy Koopman IE for a few molecules Compare Electron affinity Compare Proton affinity Protonation Site Resources Info on Results Calculations Done Method and basis set List molecules One molecule Multiple conformers, states Multiple conformers, states Basis functions used I/O files Input/output files MOL file Z-matrix wfn files Glossary Conversion Forms B to I, I to B Angle formulas Integrated heat Capacity Calculating Enthalpy Links NIST Links NIST webbook bibliographic data CCCBDB Experimental data External links Basis Set Exchange Computational Chemistry List Thermochemistry in Gaussian Minnesota Database Collection Benchmark Energy and Geometry Point Groups Thermochemistry Thermochemistry Molecules with good enthalpy A → B + C Reference states Tutorials Vibrations Why scale vibrations Zero-point energies Entropy Methyl rotor entropy Entropy and conformations Energy Getting enthalpy of formation Vertical vs adiabatic IE Thermo from calculations Electrostatics Dipole parts by point group Quadrupoles Geometry Angle formulas Cost Cost Comparison Timings Comparison Bad Calculations Geometry Bad moment of inertia Bad Calculated Bond Lengths Bad point group Worst molecules Vibrations Bad vib. 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
You are here: Calculated > Energy > Optimized > Energy

Number	Element	Mulliken
1	C	-0.180
2	N	-0.439
3	N	-0.439
4	C	-0.014
5	C	-0.014
6	H	0.314
7	H	0.314
8	H	0.229
9	H	0.229

<r²>	77.645
(<r²>)^1/2	8.812

All results from a given calculation for C3H4N2 (2H-Imidazole)

using model chemistry: LSDA/3-21G*

States and conformations

All results from a given calculation for C₃H₄N₂ (2H-Imidazole)