CCCBDB calculation results Page

using model chemistry: B1B95/aug-cc-pVTZ

States and conformations

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

State

Conformation

minimum conformation

conformer description

state description

D2H

¹A_G

yes

C2H

¹A_G

C2V

¹A₁

Conformer 1 (D2H)

Jump to S1C2 S1C3

Energy calculated at B1B95/aug-cc-pVTZ

	hartrees
Energy at 0K	-581.384162
Energy at 298.15K
HF Energy	-581.384162
Nuclear repulsion energy	79.190607

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at B1B95/aug-cc-pVTZ

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A_g	2271	2177	0.00	404.84	0.13	0.23
2	A_g	933	895	0.00	20.99	0.12	0.22
3	A_g	601	576	0.00	123.74	0.13	0.23
4	A_u	554	531	0.00	0.00	0.00	0.00
5	B_1u	2265	2171	63.65	0.00	0.00	0.00
6	B_1u	852	817	106.77	0.00	0.00	0.00
7	B_2g	154i	148i	0.00	26.61	0.75	0.86
8	B_2u	2301	2205	94.48	0.00	0.00	0.00
9	B_2u	343	329	17.98	0.00	0.00	0.00
10	B_3g	2291	2196	0.00	213.72	0.75	0.86
11	B_3g	589	565	0.00	3.71	0.75	0.86
12	B_3u	534	512	0.22	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 6689.6 cm^-1
Scaled (by 0.9585) Zero Point Vibrational Energy (zpe) 6412.0 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at B1B95/aug-cc-pVTZ

A	B	C
2.68637	0.21896	0.20246

See section I.F.4 to change rotational constant units

Geometric Data calculated at B1B95/aug-cc-pVTZ

Point Group is D_2h

Cartesians (Å)

Atom	y (Å)	z (Å)
Si1	0.000	1.063
Si2	0.000	-1.063
H3	1.248	1.849
H4	-1.248	1.849
H5	1.248	-1.849
H6	-1.248	-1.849

Atom - Atom Distances (Å)

	Si1	Si2	H3	H4	H5	H6
Si1		2.1257	1.4747	1.4747	3.1678	3.1678
Si2	2.1257		3.1678	3.1678	1.4747	1.4747
H3	1.4747	3.1678		2.4953	3.6979	4.4611
H4	1.4747	3.1678	2.4953		4.4611	3.6979
H5	3.1678	1.4747	3.6979	4.4611		2.4953
H6	3.1678	1.4747	4.4611	3.6979	2.4953

picture of Disilene state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
Si1	Si2	H5	122.214	Si1	Si2	H6	122.214
Si2	Si1	H3	122.214	Si2	Si1	H4	122.214
H3	Si1	H4	115.572	H5	Si2	H6	115.572

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B1B95/aug-cc-pVTZ Charges (e)

Number	Element	Mulliken
1	Si	0.139
2	Si	0.139
3	H	-0.069
4	H	-0.069
5	H	-0.069
6	H	-0.069

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	0.000	0.000
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-31.553	0.000	0.000
y	0.000	-29.051	0.000
z	0.000	0.000	-27.129

Traceless
	x	y	z
x	-3.463	0.000	0.000
y	0.000	0.290	0.000
z	0.000	0.000	3.173

Polar
3z²-r²	6.347
x²-y²	-2.502
xy	0.000
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	9.461	0.000	0.000
y	0.000	8.852	0.000
z	0.000	0.000	14.868

<r²> (average value of r²) Å²

<r²>	69.797
(<r²>)^1/2	8.354

Conformer 2 (C2H)

Jump to S1C1 S1C3 An error occurred on the server when processing the URL. Please contact the system administrator.

If you are the system administrator please click here to find out more about this error.

	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

All results from a given calculation for Si2H4 (Disilene)

using model chemistry: B1B95/aug-cc-pVTZ

States and conformations

Conformer 1 (D2H)

Conformer 2 (C2H)

All results from a given calculation for Si₂H₄ (Disilene)