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Silylidyne


Gas phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Quantity Value Units Method Reference Comment
Deltafgas376.66kJ/molReviewChase, 1998Data last reviewed in December, 1976
Quantity Value Units Method Reference Comment
gas,1 bar198.04J/mol*KReviewChase, 1998Data last reviewed in December, 1976

Gas Phase Heat Capacity (Shomate Equation)

Cp° = A + B*t + C*t2 + D*t3 + E/t2
H° − H°298.15= A*t + B*t2/2 + C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 − E/(2*t2) + G
    Cp = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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View table.

Temperature (K) 298. - 1400.1400. - 6000.
A 23.5512837.78273
B 13.414320.245072
C -2.700940-0.009243
D -0.5155860.020891
E 0.249938-4.759718
F 369.9087356.3308
G 224.0766233.3153
H 376.6625376.6625
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1976 Data last reviewed in December, 1976

Reaction thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

Si- + Hydrogen cation = Silylidyne

By formula: Si- + H+ = HSi

Quantity Value Units Method Reference Comment
Deltar1477. ± 11.kJ/molD-EABlondel, Chaibi, et al., 2005gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001
Quantity Value Units Method Reference Comment
Deltar1456. ± 12.kJ/molH-TSBlondel, Chaibi, et al., 2005gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001

(H2Si- bullet 4294967295Silylidyne) + Silylidyne = H2Si-

By formula: (H2Si- bullet 4294967295HSi) + HSi = H2Si-

Quantity Value Units Method Reference Comment
Deltar349. ± 9.6kJ/molN/AKasdan, Herbst, et al., 1975gas phase

Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
B - John E. Bartmess
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to HSi+ (ion structure unspecified)

Electron affinity determinations

EA (eV) Method Reference Comment
1.2771 ± 0.0087LPESKasdan, Herbst, et al., 1975B

Ionization energy determinations

IE (eV) Method Reference Comment
7.89 ± 0.07ENDBoo and Armentrout, 1987LBLHLM
7.91 ± 0.01PIBerkowitz, Greene, et al., 1987LBLHLM
8.27 ± 0.06SCarslon, Copley, et al., 1980LLK
8.04DERHuber and Herzberg, 1979LLK
7.91SRao and Lakshman, 1971LLK
8.01 ± 0.08DERDouglas and Lutz, 1970RDSH

De-protonation reactions

Si- + Hydrogen cation = Silylidyne

By formula: Si- + H+ = HSi

Quantity Value Units Method Reference Comment
Deltar1477. ± 11.kJ/molD-EABlondel, Chaibi, et al., 2005gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001; B
Quantity Value Units Method Reference Comment
Deltar1456. ± 12.kJ/molH-TSBlondel, Chaibi, et al., 2005gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001; B

Ion clustering data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

(H2Si- bullet 4294967295Silylidyne) + Silylidyne = H2Si-

By formula: (H2Si- bullet 4294967295HSi) + HSi = H2Si-

Quantity Value Units Method Reference Comment
Deltar349. ± 9.6kJ/molN/AKasdan, Herbst, et al., 1975gas phase

Constants of diatomic molecules

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through August, 1977

Symbols used in the table of constants
SymbolMeaning
State electronic state and / or symmetry symbol
Te minimum electronic energy (cm-1)
ωe vibrational constant – first term (cm-1)
ωexe vibrational constant – second term (cm-1)
ωeye vibrational constant – third term (cm-1)
Be rotational constant in equilibrium position (cm-1)
αe rotational constant – first term (cm-1)
γe rotation-vibration interaction constant (cm-1)
De centrifugal distortion constant (cm-1)
βe rotational constant – first term, centrifugal force (cm-1)
re internuclear distance (Å)
Trans. observed transition(s) corresponding to electronic state
ν00 position of 0-0 band (units noted in table)
Diatomic constants for 28SiH
StateTeomegaeomegaexeomegaeyeBealphaegammaeDebetaereTrans.nu00
E 2Sigma+ [53411.2] 1    [7.528]   [3.92E-4]  [1.5172] E larrow X V 52399.19 Z
missing citation
D 2Delta [49522.1] 1    [7.90] 2     [1.481] D larrow X V 48510.1 Z
Verma, 1965; missing citation
B 2Sigma+ [31842.2] 1    [6.62] 3 4     [1.618] B larrow X R 30830.2 3 Z
missing citation; Bollmark, Klynning, et al., 1971
C 2Sigma+ [31832.4] 5    [1.17] 3     [3.85] C larrow X R 30820.4 3 Z
Verma, 1965; Bollmark, Klynning, et al., 1971
"Slightly diffuse" weak absorption bands in the region 25600 - 26700 cm-1.
Thrush, 1960
StateTeomegaeomegaexeomegaeyeBealphaegammaeDebetaereTrans.nu00
A 2Delta 24300.4 6 1858.90 7 Z 99.175  7.4664 7 0.3445 -0.04185 [5.24E-4] 8  1.52347 A lrarrow X 9 10 R 24193.04 Z
missing citation; Douglas, 1957; missing citation; Klynning and Lindgren, 1967; Herzberg, Lagerqvist, et al., 1969
X 2Pir 0 11 2041.80 7 Z 35.51  7.4996 7 12 0.2190 0.0017 [3.97E-4]  1.52010 13  

Notes

1Only v=0 observed
2Increasing diffuseness with increasing N on account of predissociation.
3Deperturbed constants of Bollmark, Klynning, et al., 1971 whose T0 values correspond to nu00 + 1079.5 [see Klynning and Lindgren, 1967]. As in similar cases, nu00 refers to the zero-point of the Hill-VanVleck expression for the ground state. Interaction parameter HB,C = 16.1 cm-1. The v numbering of the C level is uncertain.
4Strongly predissociated above N=2.
5Only one level observed
6A0 = 3.58 Klynning and Lindgren, 1967, A1 = 3.11 Klynning and Lindgren, 1967, A2 = 2.59 Klynning and Lindgren, 1967. Discussion of second order spin-orbit splittings Veseth, 1971.
7Recalculated Herzberg, Lagerqvist, et al., 1969 from data for v=0, 1, 2 Klynning and Lindgren, 1967.
8missing note
9 Smith, 1969 gives a radiative lifetime of 0.7 mus for both SiH and SiD corresponding to f00 = 0.0037 Smith and Liszt, 1971; see also Grevesse and Sauval, 1971.
10Potential functions, Franck-Condon factors Rao and Lakshman, 1971, Smith and Liszt, 1971
11A0 = +142.83. A1 = +143.43. A2 = +144.04. Slight J dependence Klynning and Lindgren, 1967.
12For Lambda-doubling constants (p0 = 0.0819, q0 = 0.00831) see Klynning and Lindgren, 1967, missing citation; the extrapolated splitting of the v=0, J=1/2 level is Delta vfe = +0.0978 cm-1 (2932 ± 20 MHz) missing citation; ab initio calculations Wilson and Richards, 1975 predict Delta vfe= 0.1057 cm-1 (3168 MHz).
13Extensive theoretical calculations 17
14From the predissociation in B 2Sigma+ assuming dissociation into 1D + 2S at the predissociation limit Verma, 1965. According to Douglas, 1957 extrapolation of the vibrational levels in A 2Delta gives very nearly the same limit.
15From D00(SiH), I.P.(Si), and D00(SiH+) Douglas and Lutz, 1970.
16D1 = 6.08E-4, D2 = 7.36E-4.
17Hartree-Fock wavefunctions and energies Cade and Huo, 1967, charge distributions Cade, Bader, et al., 1969, spectroscopic constants Meyer and Rosmus, 1975.
18From the value for SiH, confirmed by the observed predissociation in B 2Sigma+.
19Recalculated from the data of Verma, 1965.
20Deperturbed constants of Bollmark, Klynning, et al., 1971 whose T0 values correspond to nu00 + 797.50 [see Klynning and Lindgren, 1967]. Interaction parameter HB,C = 5.87 cm-1. See 3.
21Increasing linewidth above N=8 indicating predissociation.
22A0 = 3.45, A1 = 3.42, A2 = 2.14 Klynning and Lindgren, 1967; see also Veseth, 1971.
23D1 = 1.524E-4, D2 = 1.708E-4.
24A0 = +142.73, A1 = +143.10; A2= +143.76; slight J dependence Klynning and Lindgren, 1967.
25 Klynning and Lindgren, 1967 give Lambda-doubling constants (p= 0.039, q= 0.0024).

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Constants of diatomic molecules, NIST Free Links, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Blondel, Chaibi, et al., 2005
Blondel, C.; Chaibi, W.; Delsart, C.; Drag, C.; Goldfarb, F.; Kroger, S., The electron affinities of O, Si, and S revisited with the photodetachment microscope, Eur. Phys. J. D, 2005, 33, 3, 335-342, https://doi.org/10.1140/epjd/e2005-00069-9 . [all data]

Blondel, Delsart, et al., 2001
Blondel, C.; Delsart, C.; Goldfarb, F., Electron spectrometry at the mu eV level and the electron affinities of Si and F, J. Phys. B: Atom. Mol. Opt. Phys., 2001, 34, 9, L281-L288, https://doi.org/10.1088/0953-4075/34/9/101 . [all data]

Kasdan, Herbst, et al., 1975
Kasdan, A.; Herbst, E.; Lineberger, W.C., Laser photoelectron spectrometry of the negative ions of silicon and its hydrides, J. Chem. Phys., 1975, 62, 541. [all data]

Boo and Armentrout, 1987
Boo, B.H.; Armentrout, P.B., Reaction of silicon ion (2P) with silane (SiH4, SiD4) heats of formation of SiHn, SiHn+ (n=1,2,3), and Si2Hn+ (n=0,1,2,3) remarkable isotope exchange reaction involving four hydrogen shifts, J. Am. Chem. Soc., 1987, 109, 3549. [all data]

Berkowitz, Greene, et al., 1987
Berkowitz, J.; Greene, J.P.; Cho, H.; Ruscic, B., Photoionization mass spectrometric studies of SiHn (n=1-4), J. Chem. Phys., 1987, 86, 1235. [all data]

Carslon, Copley, et al., 1980
Carslon, T.A.; Copley, J.; Duric, N.; Perman, N. -Elander; Larsson, M.; Lyyra, M., The oscillator strengths and the dissociation energy of SiH+ as determined from time resolved precision spectroscopy, Astron. Astrophys., 1980, 83, 238. [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Rao and Lakshman, 1971
Rao, T.V.R.; Lakshman, S.V.J., The true potential energy curves and Franck-Condon factors of SiH and SiH+ molecules, Physica, 1971, 56, 322. [all data]

Douglas and Lutz, 1970
Douglas, A.E.; Lutz, B.L., Spectroscopic identification of the SiH+ molecule: the A 1«pi»-X1+ system, Can. J. Phys., 1970, 48, 247. [all data]

Verma, 1965
Verma, R.D., The spectrum of SiH and SiD, Can. J. Phys., 1965, 43, 2136. [all data]

Bollmark, Klynning, et al., 1971
Bollmark, P.; Klynning, L.; Pages, P., Rotational analysis of the 3250 Å bands of SiH and SiD, Phys. Scr., 1971, 3, 219-222. [all data]

Thrush, 1960
Thrush, B.A., Absorption spectra of diatomic radicals containing boron or silicon, Nature (London), 1960, 186, 1044. [all data]

Douglas, 1957
Douglas, A.E., The spectrum of silicon hydride, Can. J. Phys., 1957, 35, 71. [all data]

Klynning and Lindgren, 1967
Klynning, L.; Lindgren, B., The spectra of silicon hydride and silicon deuteride, Ark. Fys., 1967, 33, 73. [all data]

Herzberg, Lagerqvist, et al., 1969
Herzberg, G.; Lagerqvist, A.; McKenzie, B.J., Absorption spectrum of SiH in the vacuum ultraviolet, Can. J. Phys., 1969, 47, 1889. [all data]

Veseth, 1971
Veseth, L., Second-order spin-orbit splitting in 2«DELTA» states of diatomic molecules, Physica (Amsterdam), 1971, 56, 286. [all data]

Smith, 1969
Smith, W.H., Lifetimes and total transition probabilities for NH, SiH, and SiD, J. Chem. Phys., 1969, 51, 520. [all data]

Smith and Liszt, 1971
Smith, W.H.; Liszt, H.S., Franck-Condon factors and absolute oscillator strengths for NH, SiH, S2 and SO, J. Quant. Spectrosc. Radiat. Transfer, 1971, 11, 45. [all data]

Grevesse and Sauval, 1971
Grevesse, N.; Sauval, A.J., Oscillator strengths for SiH and SiH+ deduced from the solar spectrum, J. Quant. Spectrosc. Radiat. Transfer, 1971, 11, 65. [all data]

Wilson and Richards, 1975
Wilson, I.D.L.; Richards, W.G., «LAMBDA»-type doubling in SiH molecule, Nature (London), 1975, 258, 133. [all data]

Cade and Huo, 1967
Cade, P.E.; Huo, W.M., Electronic structure of diatomic molecules. VII.A. Hartree-Fock wavefunctions and energy quantities for the ground states of the second-row hydrides, AH, J. Chem. Phys., 1967, 47, 649. [all data]

Cade, Bader, et al., 1969
Cade, P.E.; Bader, R.F.W.; Henneker, W.H.; Keaveny, I., Molecular charge distributions and chemical binding. IV. The second-row diatomic hydrides AH, J. Chem. Phys., 1969, 50, 5313. [all data]

Meyer and Rosmus, 1975
Meyer, W.; Rosmus, P., PNO-Cl and CEPA studies of electron correlation effects. III. Spectroscopic constants and dipole moment functions for the ground states of the first-row and second-row diatomic hydrides, J. Chem. Phys., 1975, 63, 2356. [all data]


Notes

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