Silicon timer
- Formula: Si3
- Molecular weight: 84.2565
- IUPAC Standard InChIKey: VJNZTIUQOVUHQB-UHFFFAOYSA-N
- CAS Registry Number: 12597-37-4
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Silicon
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Gas phase thermochemistry data
Go To: Top, Vibrational and/or electronic energy levels, 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 | 635.97 | kJ/mol | Review | Chase, 1998 | Data last reviewed in March, 1967 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 267.87 | J/mol*K | Review | Chase, 1998 | Data last reviewed in March, 1967 |
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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Temperature (K) | 298. to 6000. |
---|---|
A | 62.88678 |
B | -2.292034 |
C | 1.518324 |
D | -0.155889 |
E | -0.664449 |
F | 615.0815 |
G | 340.8504 |
H | 635.9680 |
Reference | Chase, 1998 |
Comment | Data last reviewed in March, 1967 |
Vibrational and/or electronic energy levels
Go To: Top, Gas phase thermochemistry 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: Marilyn E. Jacox
State: G
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 25753 ± 13 | T | Ne | G-X | 330 | 390 | Fulara, Freivogel, et al., 1996 | |
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 350 | T | Ne | AB | Fulara, Freivogel, et al., 1996 | ||
State: F
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 19146 ± 7 | Ne | F-X | 430 | 540 | Fulara, Freivogel, et al., 1996 | ||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 360 | T | Ne | AB | Fulara, Freivogel, et al., 1996 | ||
State: E
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 17250 ± 6 | Ne | E-X | 530 | 580 | Weltner and McLeod, 1964 | ||
Fulara, Freivogel, et al., 1996 | |||||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 2 | Bend | 250 | T | Ne | AB | Fulara, Freivogel, et al., 1996 |
State: C
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 14200 ± 160 | gas | Kitsopoulos, Chick, et al., 1990 | |||||
Xu, Taylor, et al., 1998 | |||||||
To = 12839 ± 3 | Ne | C-X | 700 | 780 | Fulara, Freivogel, et al., 1996 | ||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 480 ± 40 | gas | PE | Kitsopoulos, Chick, et al., 1990 | |
1 | Sym. stretch | 470 | T | Ne | AB | Fulara, Freivogel, et al., 1996 | |
State: B
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 11549 ± 160 | gas | Xu, Taylor, et al., 1998 | |||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 480 ± 20 | gas | PE | Xu, Taylor, et al., 1998 | |
2 | Bend | 260 ± 20 | gas | PE | Xu, Taylor, et al., 1998 | ||
State: c
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 8880 ± 80 | gas | Kitsopoulos, Chick, et al., 1990 | |||||
Xu, Taylor, et al., 1998 | |||||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 480 ± 20 | gas | PE | Xu, Taylor, et al., 1998 | |
2 | Bend | 260 ± 20 | gas | PE | Xu, Taylor, et al., 1998 | ||
State: b
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 7180 ± 80 | gas | Kitsopoulos, Chick, et al., 1990 | |||||
Xu, Taylor, et al., 1998 | |||||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 500 ± 20 | gas | PE | Xu, Taylor, et al., 1998 | |
State: A
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 3630 ± 80 | gas | Kitsopoulos, Chick, et al., 1990 | |||||
Winstead, He, et al., 1991 | |||||||
Xu, Taylor, et al., 1998 | |||||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
1 | Sym. stretch | 480 ± 25 | gas | PE EM | Kitsopoulos, Chick, et al., 1990 Winstead, He, et al., 1991 | ||
State: a
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 350 | U | gas | Arnold and Neumark, 1994 | ||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1' | 1 | Sym. stretch | 501 ± 10 | gas | TPE | Arnold and Neumark, 1994 | |
e' | 2 | Deformation | 337 ± 10 | gas | EM TPE | Kitsopoulos, Chick, et al., 1990 Winstead, He, et al., 1991 Arnold and Neumark, 1994 | |
State: X
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 550 | T | Ne | IR | Li, Van Zee, et al., 1995 |
1 | Sym. stretch | 550.6 | Ar | IR | Li, Van Zee, et al., 1995 | ||
1 | Sym. stretch | 546.7 | Kr | IR | Li, Van Zee, et al., 1995 | ||
2 | Bend | 178 ± 11 | gas | MW | McCarthy and Thaddeus, 2003 | ||
b2 | 3 | Asym. stretch | 525.5 | Ne | IR | Li, Van Zee, et al., 1995 | |
3 | Asym. stretch | 525.1 | Ar | IR | Li, Van Zee, et al., 1995 | ||
3 | Asym. stretch | 523.1 | Kr | IR | Li, Van Zee, et al., 1995 | ||
Additional references: Jacox, 1994, page 67; Jacox, 1998, page 170; Jacox, 2003, page 83; McCarthy and Thaddeus, 2003, 2
Notes
U | Upper bound |
T | Tentative assignment or approximate value |
o | Energy separation between the v = 0 levels of the excited and electronic ground states. |
References
Go To: Top, Gas phase thermochemistry data, Vibrational and/or electronic energy levels, 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]
Fulara, Freivogel, et al., 1996
Fulara, J.; Freivogel, P.; Grutter, M.; Maier, J.P.,
Electronic Absorption Spectra of Si,
J. Phys. Chem., 1996, 100, 46, 18042, https://doi.org/10.1021/jp962575h
. [all data]
Weltner and McLeod, 1964
Weltner, W., Jr.; McLeod, D., Jr.,
Spectroscopy of Silicon Carbide and Silicon Vapors Trapped in Neon and Argon Matrices at 4° and 20°K,
J. Chem. Phys., 1964, 41, 1, 235, https://doi.org/10.1063/1.1725627
. [all data]
Kitsopoulos, Chick, et al., 1990
Kitsopoulos, T.N.; Chick, C.J.; Weaver, A.; Neumark, D.M.,
Vibrationally Resolved Photoelectron Spectra of Si-3- and Si-4-,
J. Chem. Phys., 1990, 93, 8, 6108, https://doi.org/10.1063/1.459004
. [all data]
Xu, Taylor, et al., 1998
Xu, C.; Taylor, T.R.; Burton, G.R.; Neumark, D.M.,
Vibrationally resolved photoelectron spectroscopy of silicon cluster anions Si[sub n][sup -] (n=3--7),
J. Chem. Phys., 1998, 108, 4, 1395, https://doi.org/10.1063/1.475511
. [all data]
Winstead, He, et al., 1991
Winstead, C.B.; He, K.X.; Grantier, D.; Hammond, T.; Gole, J.L.,
Electric-field-enhanced laser-induced plasma spectroscopy of jet-cooled silicon trimer,
Chem. Phys. Lett., 1991, 181, 2-3, 222, https://doi.org/10.1016/0009-2614(91)90358-G
. [all data]
Arnold and Neumark, 1994
Arnold, C.C.; Neumark, D.M.,
Threshold Photodetachment Zero-Electron Kinetic Energy Spectroscopy of Si-3(-),
J. Chem. Phys., 1994, 100, 3, 1797, https://doi.org/10.1063/1.466532
. [all data]
Li, Van Zee, et al., 1995
Li, S.; Van Zee, R.J.; Weltner, W., Jr.; Raghavachari, K.,
Si3«58872»Si7. Experimental and theoretical infrared spectra,
Chem. Phys. Lett., 1995, 243, 3-4, 275, https://doi.org/10.1016/0009-2614(95)00836-S
. [all data]
McCarthy and Thaddeus, 2003
McCarthy, M.; Thaddeus, P.,
Rotational Spectrum and Structure of Si3,
Phys. Rev. Lett., 2003, 90, 21, 213003, https://doi.org/10.1103/PhysRevLett.90.213003
. [all data]
Jacox, 1994
Jacox, M.E.,
Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]
Jacox, 1998
Jacox, M.E.,
Vibrational and electronic energy levels of polyatomic transient molecules: supplement A,
J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017
. [all data]
Jacox, 2003
Jacox, M.E.,
Vibrational and electronic energy levels of polyatomic transient molecules: supplement B,
J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629
. [all data]
McCarthy and Thaddeus, 2003, 2
McCarthy, M.; Thaddeus, P.,
The Radio Spectrum of Si,
Astrophys. J. Lett., 2003, 592, 2, L91, https://doi.org/10.1086/375728
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Vibrational and/or electronic energy levels, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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