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Experimental data for HSiF (fluorosilylene)

22 02 02 11 45
Other names
silylene, fluoro-;
InChI=1S/FHSi/c1-2/h2H [SiH]F
State Conformation
1A' CS
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency Intensity Comment Description
Fundamental(cm-1) Harmonic(cm-1) Reference (km mol-1) unc. Reference
1 A' 1930   webbook       SiH stretch
2 A' 861           bend
3 A' 838           SiF stretch

vibrational zero-point energy: 1814.4 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for HSiF (fluorosilylene).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
7.57917 0.56425 0.52365 1985Suz/Hak:3580-3583

Calculated rotational constants for HSiF (fluorosilylene).
Product of moments of inertia moments of inertia
2139.192amu3Å6   9.79530202351172E-117gm3 cm6
Geometric Data
picture of fluorosilylene

Point Group Cs

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees
Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rSiH 1.528 0.005 3 1997Har/Hos:4367-4375
rSiF 1.603 0.003 2 1997Har/Hos:4367-4375 re
aHSiF 96.9 0.5 2 1 3 1997Har/Hos:4367-4375

Atom x (Å) y (Å) z (Å)
Si1 0.0633 -0.5941 0.0000
F2 0.0633 1.0109 0.0000
H3 -1.4553 -0.7806 0.0000

Atom - Atom Distances bond lengths
Distances in Å
  Si1 F2 H3
Si1   1.60501.5300
F2 1.6050   2.3485
H3 1.53002.3485  

Calculated geometries for HSiF (fluorosilylene).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle
F2 Si1 H3 97.000

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
F-Si 1
H-Si 1

Atom 1 Atom 2
Si1 F2
Si1 H3
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A'
23260.0223 1 1985Suz/Hak:3580-3583 1A"
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
State Config State description Conf description Exp. min. Dipole (Debye) Reference comment Point Group Components
x y z total dipole quadrupole
1 1 1A' Cs True           Cs 2 3
2 1 1A" Cs          
Experimental dipole measurement abbreviations: MW microwave; DT Dielectric with Temperature variation; DR Indirect (usually an upper limit); MB Molecular beam
Calculated electric dipole moments for HSiF (fluorosilylene).
Electric quadrupole moment quadrupole
State Config State description Conf description Exp. min. Quadrupole (D Å) Reference comment Point Group Components
xx yy zz dipole quadrupole
1 1 1A' Cs True       Cs 2 3
2 1 1A" Cs      

Calculated electric quadrupole moments for HSiF (fluorosilylene).

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squib reference DOI
1985Suz/Hak:3580-3583 T Suzuki, K Hakuta, S Saito, E Hirota "Doppler-limited dye laser excitation spectroscopy of the à 1A’’(000)–X̃ 1A’(000) band of HSiF" J. Chem. Phys. 82, 3580 (1985) 10.1063/1.448915
1997Har/Hos:4367-4375 WW Harper, DA Hostutler, DJ Clouthier "Pulsed discharge jet spectroscopy of DSiF and the equilibrium molecular structure of monofluorosilylene" J. Chem. Phys. 106, 4367 (1997) 10.1063/1.473484
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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