Silylidyne
- Formula: HSi
- Molecular weight: 29.0934
- IUPAC Standard InChIKey: QHGSGZLLHBKSAH-UHFFFAOYSA-N
- CAS Registry Number: 13774-94-2
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References, Notes
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 |
---|---|---|---|---|---|
ΔfH°gas | 90.024 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1976 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 47.333 | cal/mol*K | Review | Chase, 1998 | Data 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 (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 1400. | 1400. to 6000. |
---|---|---|
A | 5.628892 | 9.030290 |
B | 3.206100 | 0.058574 |
C | -0.645540 | -0.002209 |
D | -0.123228 | 0.004993 |
E | 0.059737 | -1.137600 |
F | 88.41030 | 85.16511 |
G | 53.55559 | 55.76370 |
H | 90.02450 | 90.02450 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in December, 1976 | Data last reviewed in December, 1976 |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References, Notes
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- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 353.1 ± 2.7 | kcal/mol | D-EA | Blondel, Chaibi, et al., 2005 | gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001 |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 347.9 ± 2.8 | kcal/mol | H-TS | Blondel, Chaibi, et al., 2005 | gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001 |
(H2Si- • 4294967295) +
= H2Si-
By formula: (H2Si- • 4294967295HSi) + HSi = H2Si-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 83.4 ± 2.3 | kcal/mol | N/A | Kasdan, Herbst, et al., 1975 | gas phase |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Constants of diatomic molecules, References, Notes
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 ± 0.0087 | LPES | Kasdan, Herbst, et al., 1975 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
7.89 ± 0.07 | END | Boo and Armentrout, 1987 | LBLHLM |
7.91 ± 0.01 | PI | Berkowitz, Greene, et al., 1987 | LBLHLM |
8.27 ± 0.06 | S | Carslon, Copley, et al., 1980 | LLK |
8.04 | DER | Huber and Herzberg, 1979 | LLK |
7.91 | S | Rao and Lakshman, 1971 | LLK |
8.01 ± 0.08 | DER | Douglas and Lutz, 1970 | RDSH |
De-protonation reactions
Si- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 353.1 ± 2.7 | kcal/mol | D-EA | Blondel, Chaibi, et al., 2005 | gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 347.9 ± 2.8 | kcal/mol | H-TS | Blondel, Chaibi, et al., 2005 | gas phase; (28)Si: 1.3895213(13) eV; revised analysis of Blondel, Delsart, et al., 2001; B |
Constants of diatomic molecules
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References, Notes
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
Symbol | Meaning |
---|---|
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) |
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
E 2Σ+ | [53411.2] 1 | [7.528] | [3.92E-4] | [1.5172] | E ← X V | 52399.19 Z | ||||||
↳missing citation | ||||||||||||
D 2Δ | [49522.1] 1 | [7.90] 2 | [1.481] | D ← X V | 48510.1 Z | |||||||
↳Verma, 1965; missing citation | ||||||||||||
B 2Σ+ | [31842.2] 1 | [6.62] 3 4 | [1.618] | B ← X R | 30830.2 3 Z | |||||||
↳missing citation; Bollmark, Klynning, et al., 1971 | ||||||||||||
C 2Σ+ | [31832.4] 5 | [1.17] 3 | [3.85] | C ← 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
A 2Δ | 24300.4 6 | 1858.90 7 Z | 99.175 | 7.4664 7 | 0.3445 | -0.04185 | [5.24E-4] 8 | 1.52347 | A ↔ X 9 10 R | 24193.04 Z | ||
↳missing citation; Douglas, 1957; missing citation; Klynning and Lindgren, 1967; Herzberg, Lagerqvist, et al., 1969 | ||||||||||||
X 2Πr | 0 11 | 2041.80 7 Z | 35.51 | 7.4996 7 12 | 0.2190 | 0.0017 | [3.97E-4] | 1.52010 13 |
Notes
1 | Only v=0 observed |
2 | Increasing diffuseness with increasing N on account of predissociation. |
3 | Deperturbed constants of Bollmark, Klynning, et al., 1971 whose T0 values correspond to ν00 + 1079.5 [see Klynning and Lindgren, 1967]. As in similar cases, ν00 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. |
4 | Strongly predissociated above N=2. |
5 | Only one level observed |
6 | A0 = 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. |
7 | Recalculated Herzberg, Lagerqvist, et al., 1969 from data for v=0, 1, 2 Klynning and Lindgren, 1967. |
8 | missing note |
9 | Smith, 1969 gives a radiative lifetime of 0.7 μs for both SiH and SiD corresponding to f00 = 0.0037 Smith and Liszt, 1971; see also Grevesse and Sauval, 1971. |
10 | Potential functions, Franck-Condon factors Rao and Lakshman, 1971, Smith and Liszt, 1971 |
11 | A0 = +142.83. A1 = +143.43. A2 = +144.04. Slight J dependence Klynning and Lindgren, 1967. |
12 | For Λ-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 Δ vfe = +0.0978 cm-1 (2932 ± 20 MHz) missing citation; ab initio calculations Wilson and Richards, 1975 predict Δ vfe= 0.1057 cm-1 (3168 MHz). |
13 | Extensive theoretical calculations 17 |
14 | From the predissociation in B 2Σ+ assuming dissociation into 1D + 2S at the predissociation limit Verma, 1965. According to Douglas, 1957 extrapolation of the vibrational levels in A 2Δ gives very nearly the same limit. |
15 | From D00(SiH), I.P.(Si), and D00(SiH+) Douglas and Lutz, 1970. |
16 | D1 = 6.08E-4, D2 = 7.36E-4. |
17 | Hartree-Fock wavefunctions and energies Cade and Huo, 1967, charge distributions Cade, Bader, et al., 1969, spectroscopic constants Meyer and Rosmus, 1975. |
18 | From the value for SiH, confirmed by the observed predissociation in B 2Σ+. |
19 | Recalculated from the data of Verma, 1965. |
20 | Deperturbed constants of Bollmark, Klynning, et al., 1971 whose T0 values correspond to ν00 + 797.50 [see Klynning and Lindgren, 1967]. Interaction parameter HB,C = 5.87 cm-1. See 3. |
21 | Increasing linewidth above N=8 indicating predissociation. |
22 | A0 = 3.45, A1 = 3.42, A2 = 2.14 Klynning and Lindgren, 1967; see also Veseth, 1971. |
23 | D1 = 1.524E-4, D2 = 1.708E-4. |
24 | A0 = +142.73, A1 = +143.10; A2= +143.76; slight J dependence Klynning and Lindgren, 1967. |
25 | Klynning and Lindgren, 1967 give Λ-doubling constants (p= 0.039, q= 0.0024). |
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, 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 1π-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 2Δ 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.,
Λ-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
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References
- Symbols used in this document:
EA Electron affinity S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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