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, Gas phase ion energetics data, 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 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, 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.
Data compiled as indicated in comments:
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
2.400 ± 0.030 | N/A | Peppernick, Gunaratne, et al., 2010 | Stated electron affinity is the Vertical Detachment Energy; B |
2.30177 ± 0.00087 | ZEKE | Arnold and Neumark, 1994 | B |
2.33 | LPES | Kitsopoulos, Chick, et al., 1990 | B |
2.00 ± 0.20 | LPES | Cheshnovsky, Yang, et al., 1987 | EA given is Vertical Detachment Energy. Adiabatic EA est as up to 1 eV smaller; B |
<2.60011 | IMRB | Mandich, Bondybey, et al., 1987 | The values from this reference are ca. 0.4-0.8 eV more bound than from other references; B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.0 ± 0.3 | EI | Drowart, DeMaria, et al., 1958 | RDSH |
Vibrational and/or electronic energy levels
Go To: Top, Gas phase 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: 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, Gas phase ion energetics 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]
Peppernick, Gunaratne, et al., 2010
Peppernick, S.J.; Gunaratne, K.D.D.; Sayres, S.G.; Castleman, A.W.,
Photoelectron imaging of small silicon cluster anions, Si-n- (n=2-7),
J. Chem. Phys., 2010, 132, 4, 044302, https://doi.org/10.1063/1.3299271
. [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]
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]
Cheshnovsky, Yang, et al., 1987
Cheshnovsky, O.; Yang, S.H.; Pettiette, C.L.; Craycraft, M.J.; Liu, Y.; Smalley, R.E.,
Ultraviolet Photoelectron Spectroscopy of Semiconductor Clusters: Silicon and Germanium,
Chem. Phys. Lett., 1987, 138, 2-3, 119, https://doi.org/10.1016/0009-2614(87)80353-6
. [all data]
Mandich, Bondybey, et al., 1987
Mandich, M.L.; Bondybey, V.E.; Reents, W.D.,
Reactive Etching of Positive and Negative Silicon Cluster Ions by Nitrogen Dioxide,
J. Chem. Phys., 1987, 86, 7, 4245, https://doi.org/10.1063/1.451885
. [all data]
Drowart, DeMaria, et al., 1958
Drowart, J.; DeMaria, G.; Inghram, M.G.,
Thermodynamic study of SiC utilizing a mass spectrometer,
J. Chem. Phys., 1958, 29, 1015. [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]
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]
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, Gas phase ion energetics data, Vibrational and/or electronic energy levels, 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 - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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