CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	TD	¹A₁

Energy calculated at mPW1PW91/3-21G*

	hartrees
Energy at 0K	-446.860522
Energy at 298.15K	-446.871922
Nuclear repulsion energy	245.015457

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 mPW1PW91/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁	3046	2893	0.00
2	A₁	1361	1293	0.00
3	A₁	594	565	0.00
4	A₂	160	152	0.00
5	E	3125	2968	0.00
5	E	3125	2968	0.00
6	E	1526	1449	0.00
6	E	1526	1449	0.00
7	E	877	833	0.00
7	E	877	833	0.00
8	E	183	174	0.00
8	E	183	174	0.00
9	T₁	3125	2968	0.00
9	T₁	3125	2968	0.00
9	T₁	3125	2968	0.00
10	T₁	1522	1445	0.00
10	T₁	1522	1445	0.00
10	T₁	1522	1445	0.00
11	T₁	729	692	0.00
11	T₁	729	692	0.00
11	T₁	729	692	0.00
12	T₁	164	155	0.00
12	T₁	164	155	0.00
12	T₁	164	155	0.00
13	T₂	3129	2971	33.68
13	T₂	3129	2971	33.68
13	T₂	3129	2971	33.68
14	T₂	3044	2891	6.59
14	T₂	3044	2891	6.59
14	T₂	3044	2891	6.59
15	T₂	1541	1463	11.41
15	T₂	1541	1463	11.41
15	T₂	1541	1463	11.41
16	T₂	1357	1288	63.84
16	T₂	1357	1288	63.84
16	T₂	1357	1288	63.84
17	T₂	940	893	169.80
17	T₂	940	893	169.80
17	T₂	940	893	169.80
18	T₂	721	685	9.42
18	T₂	721	685	9.42
18	T₂	721	685	9.42
19	T₂	219	208	1.87
19	T₂	219	208	1.87
19	T₂	219	208	1.87

Unscaled Zero Point Vibrational Energy (zpe) 33027.1 cm^-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 31362.5 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 mPW1PW91/3-21G*

A	B	C
0.10248	0.10248	0.10248

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

Geometric Data calculated at mPW1PW91/3-21G*

Point Group is T_d

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
Si1	0.000	0.000	0.000
C2	1.090	1.090	1.090
C3	-1.090	-1.090	1.090
C4	-1.090	1.090	-1.090
C5	1.090	-1.090	-1.090
H6	1.736	0.481	1.736
H7	1.736	1.736	0.481
H8	0.481	1.736	1.736
H9	-1.736	-1.736	0.481
H10	-0.481	-1.736	1.736
H11	-1.736	-0.481	1.736
H12	-1.736	0.481	-1.736
H13	-1.736	1.736	-0.481
H14	-0.481	1.736	-1.736
H15	1.736	-1.736	-0.481
H16	0.481	-1.736	-1.736
H17	1.736	-0.481	-1.736

Atom - Atom Distances (Å)

	Si1	C2	C3	C4	C5	H6	H7	H8	H9	H10	H11	H12	H13	H14	H15	H16	H17
Si1		1.8879	1.8879	1.8879	1.8879	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015	2.5015
C2	1.8879		3.0829	3.0829	3.0829	1.0975	1.0975	1.0975	4.0422	3.2970	3.2970	4.0422	3.2970	3.2970	3.2970	4.0422	3.2970
C3	1.8879	3.0829		3.0829	3.0829	3.2970	4.0422	3.2970	1.0975	1.0975	1.0975	3.2970	3.2970	4.0422	3.2970	3.2970	4.0422
C4	1.8879	3.0829	3.0829		3.0829	4.0422	3.2970	3.2970	3.2970	4.0422	3.2970	1.0975	1.0975	1.0975	4.0422	3.2970	3.2970
C5	1.8879	3.0829	3.0829	3.0829		3.2970	3.2970	4.0422	3.2970	3.2970	4.0422	3.2970	4.0422	3.2970	1.0975	1.0975	1.0975
H6	2.5015	1.0975	3.2970	4.0422	3.2970		1.7741	1.7741	4.3058	3.1354	3.6025	4.9094	4.3058	4.3058	3.1354	4.3058	3.6025
H7	2.5015	1.0975	4.0422	3.2970	3.2970	1.7741		1.7741	4.9094	4.3058	4.3058	4.3058	3.6025	3.1354	3.6025	4.3058	3.1354
H8	2.5015	1.0975	3.2970	3.2970	4.0422	1.7741	1.7741		4.3058	3.6025	3.1354	4.3058	3.1354	3.6025	4.3058	4.9094	4.3058
H9	2.5015	4.0422	1.0975	3.2970	3.2970	4.3058	4.9094	4.3058		1.7741	1.7741	3.1354	3.6025	4.3058	3.6025	3.1354	4.3058
H10	2.5015	3.2970	1.0975	4.0422	3.2970	3.1354	4.3058	3.6025	1.7741		1.7741	4.3058	4.3058	4.9094	3.1354	3.6025	4.3058
H11	2.5015	3.2970	1.0975	3.2970	4.0422	3.6025	4.3058	3.1354	1.7741	1.7741		3.6025	3.1354	4.3058	4.3058	4.3058	4.9094
H12	2.5015	4.0422	3.2970	1.0975	3.2970	4.9094	4.3058	4.3058	3.1354	4.3058	3.6025		1.7741	1.7741	4.3058	3.1354	3.6025
H13	2.5015	3.2970	3.2970	1.0975	4.0422	4.3058	3.6025	3.1354	3.6025	4.3058	3.1354	1.7741		1.7741	4.9094	4.3058	4.3058
H14	2.5015	3.2970	4.0422	1.0975	3.2970	4.3058	3.1354	3.6025	4.3058	4.9094	4.3058	1.7741	1.7741		4.3058	3.6025	3.1354
H15	2.5015	3.2970	3.2970	4.0422	1.0975	3.1354	3.6025	4.3058	3.6025	3.1354	4.3058	4.3058	4.9094	4.3058		1.7741	1.7741
H16	2.5015	4.0422	3.2970	3.2970	1.0975	4.3058	4.3058	4.9094	3.1354	3.6025	4.3058	3.1354	4.3058	3.6025	1.7741		1.7741
H17	2.5015	3.2970	4.0422	3.2970	1.0975	3.6025	3.1354	4.3058	4.3058	4.3058	4.9094	3.6025	4.3058	3.1354	1.7741	1.7741

picture of tetramethylsilane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
Si1	C2	H6	111.054	Si1	C2	H7	111.054
Si1	C2	H8	111.054	Si1	C3	H9	111.054
Si1	C3	H10	111.054	Si1	C3	H11	111.054
Si1	C4	H12	111.054	Si1	C4	H13	111.054
Si1	C4	H14	111.054	Si1	C5	H15	111.054
Si1	C5	H16	111.054	Si1	C5	H17	111.054
C2	Si1	C3	109.471	C2	Si1	C4	109.471
C2	Si1	C5	109.471	C3	Si1	C4	109.471
C3	Si1	C5	109.471	C4	Si1	C5	109.471
H6	C2	H7	107.844	H6	C2	H8	107.844
H7	C2	H8	107.844	H9	C3	H10	107.844
H9	C3	H11	107.844	H10	C3	H11	107.844
H12	C4	H13	107.844	H12	C4	H14	107.844
H13	C4	H14	107.844	H15	C5	H16	107.844
H15	C5	H17	107.844	H16	C5	H17	107.844

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G* Charges (e)

Number	Element	Mulliken
1	Si	1.287
2	C	-0.947
3	C	-0.947
4	C	-0.947
5	C	-0.947
6	H	0.208
7	H	0.208
8	H	0.208
9	H	0.208
10	H	0.208
11	H	0.208
12	H	0.208
13	H	0.208
14	H	0.208
15	H	0.208
16	H	0.208
17	H	0.208

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	-41.295	0.000	0.000
y	0.000	-41.295	0.000
z	0.000	0.000	-41.295

Traceless
	x	y	z
x	0.000	0.000	0.000
y	0.000	0.000	0.000
z	0.000	0.000	0.000

Polar
3z²-r²	0.000
x²-y²	0.000
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	8.764	0.000	0.000
y	0.000	8.764	0.000
z	0.000	0.000	8.764

<r²> (average value of r²) Å²

<r²>	186.417
(<r²>)^1/2	13.653

All results from a given calculation for Si(CH₃)₄ (tetramethylsilane)

using model chemistry: mPW1PW91/3-21G*

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

All results from a given calculation for Si(CH3)4 (tetramethylsilane)

using model chemistry: mPW1PW91/3-21G*

States and conformations

All results from a given calculation for Si(CH₃)₄ (tetramethylsilane)