Selected ATcT [1, 2] enthalpy of formation based on version 1.176 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.172 to include species related to Criegee intermediates that are involved in several ongoing studies[4].

Silicate

Formula: [SiO2]- (g)

CAS RN: 53095-83-3

ATcT ID: 53095-83-3*0

SMILES: O=[Si-]=O

InChI: InChI=1S/O2Si/c1-3-2/q-1

InChIKey: KJWXXCLQZAEGKT-UHFFFAOYSA-N

Hills Formula: O2Si1-

2D Image:

Aliases: [SiO2]-; Silicate; Silicate ion; Silicate anion; Silicate ion (1-); Silicon dioxide anion; Silicon dioxide ion (1-); Silicon oxide anion; Silicon oxide ion (1-); Silicon (IV) oxide anion; Silicon (IV) oxide ion (1-)

Relative Molecular Mass: 60.08485 ± 0.00067

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-477.5	-478.3	± 2.6	kJ/mol

3D Image of [SiO2]- (g)

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Top contributors to the provenance of Δ_fH° of [SiO2]- (g)

The 17 contributors listed below account for 90.1% of the provenance of Δ_fH° of [SiO2]- (g).

Please note: The list is limited to 20 most important contributors or, if less, a number sufficient to account for 90% of the provenance. The Reference acts as a further link to the relevant references and notes for the measurement. The Measured Quantity is normaly given in the original units; in cases where we have reinterpreted the original measurement, the listed value may differ from that given by the authors. The quoted uncertainty is the a priori uncertainty used as input when constructing the initial Thermochemical Network, and corresponds either to the value proposed by the original authors or to our estimate; if an additional multiplier is given in parentheses immediately after the prior uncertainty, it corresponds to the factor by which the prior uncertainty needed to be multiplied during the ATcT analysis in order to make that particular measurement consistent with the prevailing knowledge contained in the Thermochemical Network.

Contribution (%)	TN ID	Reaction	Measured Quantity	Reference
15.7	8498.4	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 338.84 ± 1.50 kcal/mol	Ruscic W1RO
13.8	8498.2	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 339.58 ± 1.60 kcal/mol	Ruscic G4
12.4	8496.5	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.036 ± 0.050 eV	Ruscic W1RO
11.9	8498.1	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 340.92 ± 1.72 kcal/mol	Ruscic G3X
8.3	8496.3	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.127 ± 0.061 eV	Ruscic G4
7.5	8498.3	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 339.80 ± 2.16 kcal/mol	Ruscic CBS-n
4.3	8496.2	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.074 ± 0.085 eV	Ruscic G3X
3.6	8496.4	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.024 ± 0.092 eV	Ruscic CBS-n
3.1	8496.1	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.1 ± 0.1 eV	Wang 1996
1.5	8494.4	SiO2 (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 291.89 ± 1.50 kcal/mol	Ruscic W1RO
1.4	8721.4	2 SiH2O (g) → SiH4 (g) + SiO2 (g)	Δ_rH°(0 K) = -11.38 ± 0.9 kcal/mol	Ruscic W1RO
1.3	8494.2	SiO2 (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 290.52 ± 1.60 kcal/mol	Ruscic G4
1.2	8494.1	SiO2 (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 293.09 ± 1.72 kcal/mol	Ruscic G3X
1.1	8721.2	2 SiH2O (g) → SiH4 (g) + SiO2 (g)	Δ_rH°(0 K) = -11.06 ± 1.0 kcal/mol	Ruscic G4
0.9	8721.1	2 SiH2O (g) → SiH4 (g) + SiO2 (g)	Δ_rH°(0 K) = -11.78 ± 1.1 kcal/mol	Ruscic G3X
0.7	8494.3	SiO2 (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 293.12 ± 2.16 kcal/mol	Ruscic CBS-n
0.7	8538.1	Si (cr,l) + 2 F2 (g) → SiF4 (g)	Δ_rH°(298.15 K) = -385.98 ± 0.19 kcal/mol	Wise 1963, Wise 1963, Wise 1962

Top 10 species with enthalpies of formation correlated to the Δ_fH° of [SiO2]- (g)

Please note: The correlation coefficients are obtained by renormalizing the off-diagonal elements of the covariance matrix by the corresponding variances.
The correlation coefficient is a number from -1 to 1, with 1 representing perfectly correlated species, -1 representing perfectly anti-correlated species, and 0 representing perfectly uncorrelated species.

Correlation Coefficent (%)	Species Name	Formula	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
45.9	Dioxosilane	SiO2 (g)	-277.9	-279.3	± 2.0	kJ/mol	60.08430 ± 0.00067	7631-86-9*0
28.0	Silanone	SiH2O (g)	-93.78	-99.12	± 0.99	kJ/mol	46.10078 ± 0.00045	22755-01-7*0
22.1	Dioxosilane cation	[SiO2]+ (g)	946.3	946.2	± 2.8	kJ/mol	60.08375 ± 0.00067	59458-81-0*0
19.9	Silicon atom tetracation	[Si]+4 (g)	10401.10	10404.08	± 0.56	kJ/mol	28.08331 ± 0.00030	22537-24-2*0
19.9	Silicon atom trication	[Si]+3 (g)	6045.58	6048.56	± 0.56	kJ/mol	28.08385 ± 0.00030	14175-56-5*0
19.9	Silicon atom dication	[Si]+2 (g)	2814.00	2816.98	± 0.56	kJ/mol	28.08440 ± 0.00030	14175-55-4*0
19.9	Silicon cation	Si+ (g)	1236.86	1240.99	± 0.56	kJ/mol	28.08495 ± 0.00030	14067-07-3*0
19.9	Silicon anion	Si- (g)	316.28	319.26	± 0.56	kJ/mol	28.08605 ± 0.00030	14337-02-1*0
19.9	Silicon	Si (g)	450.34	454.68	± 0.56	kJ/mol	28.08550 ± 0.00030	7440-21-3*0
17.1	Silanol	SiH3OH (g)	-271.0	-282.7	± 1.2	kJ/mol	48.11666 ± 0.00051	14475-38-8*0

Most Influential reactions involving [SiO2]- (g)

Please note: The list, which is based on a hat (projection) matrix analysis, is limited to no more than 20 largest influences.

Influence Coefficient	TN ID	Reaction	Measured Quantity	Reference
0.253	8496.5	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.036 ± 0.050 eV	Ruscic W1RO
0.170	8496.3	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.127 ± 0.061 eV	Ruscic G4
0.164	8498.4	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 338.84 ± 1.50 kcal/mol	Ruscic W1RO
0.144	8498.2	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 339.58 ± 1.60 kcal/mol	Ruscic G4
0.125	8498.1	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 340.92 ± 1.72 kcal/mol	Ruscic G3X
0.087	8496.2	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.074 ± 0.085 eV	Ruscic G3X
0.079	8498.3	[SiO2]- (g) → Si (g) + 2 O (g)	Δ_rH°(0 K) = 339.80 ± 2.16 kcal/mol	Ruscic CBS-n
0.075	8496.4	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.024 ± 0.092 eV	Ruscic CBS-n
0.063	8496.1	[SiO2]- (g) → SiO2 (g)	Δ_rH°(0 K) = 2.1 ± 0.1 eV	Wang 1996

References

1		B. Ruscic, R. E. Pinzon, M. L. Morton, G. von Laszewski, S. Bittner, S. G. Nijsure, K. A. Amin, M. Minkoff, and A. F. Wagner, Introduction to Active Thermochemical Tables: Several "Key" Enthalpies of Formation Revisited. J. Phys. Chem. A 108, 9979-9997 (2004) [DOI: 10.1021/jp047912y]
2		B. Ruscic, R. E. Pinzon, G. von Laszewski, D. Kodeboyina, A. Burcat, D. Leahy, D. Montoya, and A. F. Wagner, Active Thermochemical Tables: Thermochemistry for the 21^st Century. J. Phys. Conf. Ser. 16, 561-570 (2005) [DOI: 10.1088/1742-6596/16/1/078]
3		B. Ruscic and D. H. Bross, Active Thermochemical Tables (ATcT) values based on ver. 1.176 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		T. L. Nguyen et al, ongoing studies (2024)
5		B. Ruscic, Uncertainty Quantification in Thermochemistry, Benchmarking Electronic Structure Computations, and Active Thermochemical Tables. Int. J. Quantum Chem. 114, 1097-1101 (2014) [DOI: 10.1002/qua.24605]
6		B. Ruscic and D. H. Bross, Thermochemistry Computer Aided Chem. Eng. 45, 3-114 (2019) [DOI: 10.1016/B978-0-444-64087-1.00001-2]

Formula

The aggregate state is given in parentheses following the formula, such as: g - gas-phase, cr - crystal, l - liquid, etc.

Uncertainties

The listed uncertainties correspond to estimated 95% confidence limits, as customary in thermochemistry (see, for example, Ruscic [5] and Ruscic and Bross[6]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.000₅ kJ/mol.

Website Functionality Credits

The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict.
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/.

Acknowledgement

This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.