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

State	Conformation	minimum conformation	conformer description	state description
1	1	no	D2H	¹A_G
1	2	yes	C2H	¹A_G
1	3	no	C2V	¹A₁

	hartrees
Energy at 0K	-580.328457
Energy at 298.15K
HF Energy	-580.113603
Nuclear repulsion energy	78.421116

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	A_g	2230	2147
2	A_g	937	902
3	A_g	574	553
4	A_u	507	488
5	B_1u	2224	2141
6	B_1u	865	833
7	B_2g	393i	378i
8	B_2u	2257	2173
9	B_2u	355	342
10	B_3g	2247	2164
11	B_3g	592	570
12	B_3u	458	441

Atom	y (Å)	z (Å)
Si1	0.000	1.076
Si2	0.000	-1.076
H3	1.258	1.861
H4	-1.258	1.861
H5	1.258	-1.861
H6	-1.258	-1.861

	Si1	Si2	H3	H4	H5	H6
Si1		2.1513	1.4824	1.4824	3.1942	3.1942
Si2	2.1513		3.1942	3.1942	1.4824	1.4824
H3	1.4824	3.1942		2.5151	3.7210	4.4913
H4	1.4824	3.1942	2.5151		4.4913	3.7210
H5	3.1942	1.4824	3.7210	4.4913		2.5151
H6	3.1942	1.4824	4.4913	3.7210	2.5151

All results from a given calculation for Si₂H₄ (Disilene)

using model chemistry: QCISD(T)/6-311G*

States and conformations

Conformer 1 (D2H)

Conformer 2 (C2H)

Conformer 3 (C2V)

	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

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
Si1	Si2	H5	121.969	Si1	Si2	H6	121.969
Si2	Si1	H3	121.969	Si2	Si1	H4	121.969
H3	Si1	H4	116.063	H5	Si2	H6	116.063

	hartrees
Energy at 0K	-580.331650
Energy at 298.15K
HF Energy	-580.112234
Nuclear repulsion energy	77.575174

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	A_g	2196	2115
2	A_g	943	908
3	A_g	557	536
4	A_g	403	388
5	A_u	2221	2138
6	A_u	512	493
7	A_u	350	337
8	B_g	2210	2128
9	B_g	628	605
10	B_u	2192	2110
11	B_u	915	881
12	B_u	443	426

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.095	0.000
Si2	0.000	-1.095	0.000
H3	0.475	1.781	1.233
H4	0.475	1.781	-1.233
H5	-0.475	-1.781	1.233
H6	-0.475	-1.781	-1.233

	Si1	Si2	H3	H4	H5	H6
Si1		2.1902	1.4891	1.4891	3.1651	3.1651
Si2	2.1902		3.1651	3.1651	1.4891	1.4891
H3	1.4891	3.1651		2.4668	3.6863	4.4355
H4	1.4891	3.1651	2.4668		4.4355	3.6863
H5	3.1651	1.4891	3.6863	4.4355		2.4668
H6	3.1651	1.4891	4.4355	3.6863	2.4668

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
Si1	Si2	H5	117.421	Si1	Si2	H6	117.421
Si2	Si1	H3	117.421	Si2	Si1	H4	117.421
H3	Si1	H4	111.848	H5	Si2	H6	111.848

	hartrees
Energy at 0K	-580.285708
Energy at 298.15K
HF Energy	-580.074019
Nuclear repulsion energy	72.776407

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)
1	A₁	2048	1972
2	A₁	1642	1581
3	A₁	933	899
4	A₁	408	393
5	A₁	387	373
6	A₂	1351	1301
7	A₂	645	621
8	B₁	1265	1218
9	B₁	895	862
10	B₂	2025	1950
11	B₂	1423	1370
12	B₂	766	738

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	1.322	-0.092
Si2	0.000	-1.322	-0.092
H3	-1.032	0.000	-0.139
H4	1.032	0.000	-0.139
H5	0.000	1.371	1.428
H6	0.000	-1.371	1.428

	Si1	Si2	H3	H4	H5	H6
Si1		2.6443	1.6781	1.6781	1.5209	3.0928
Si2	2.6443		1.6781	1.6781	3.0928	1.5209
H3	1.6781	1.6781		2.0645	2.3245	2.3245
H4	1.6781	1.6781	2.0645		2.3245	2.3245
H5	1.5209	3.0928	2.3245	2.3245		2.7426
H6	3.0928	1.5209	2.3245	2.3245	2.7426

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
Si1	Si2	H5	29.440	Si1	Si2	H6	91.853
Si2	Si1	H3	38.011	Si2	Si1	H4	38.011
H3	Si1	H4	75.927	H5	Si2	H6	62.413

All results from a given calculation for Si2H4 (Disilene)

using model chemistry: QCISD(T)/6-311G*

States and conformations

Conformer 1 (D2H)

Conformer 2 (C2H)

Conformer 3 (C2V)

All results from a given calculation for Si₂H₄ (Disilene)