Correlation between the standard formation enthalpy and the path index of pyridine-derivatives

2000 ◽  
Vol 5 (2) ◽  
pp. 229-232 ◽  
Author(s):  
Li Liang-chao ◽  
Liao Gui-ying ◽  
Jiang Sheng-bin ◽  
Wang Ying-xi ◽  
Sun Ju-tang
Keyword(s):  
Formation Enthalpy ◽  
Pyridine Derivatives ◽  
Path Index ◽  
Standard Formation Enthalpy

Correlation model to estimate the thermodynamic properties

2017 ◽  
Vol 16 (06) ◽  
pp. 1750050
Author(s):  
O. Yu. Goncharov
Keyword(s):  
Heat Capacity ◽  
Thermodynamic Properties ◽  
Taylor Expansion ◽  
Estimation Error ◽  
Formation Enthalpy ◽  
Correlation Model ◽  
Entropy Formula ◽  
Analytic Relationship ◽  
Standard Formation Enthalpy

A technique for constructing the correlation dependencies of the thermodynamic properties of similar compounds was proposed. This technique is based on the Taylor expansion in the supposed analytic relationship between properties. The constructed correlation dependencies were used to estimate the thermodynamic properties of the condensed bromides and iodides of hafnium HfGn (G [Formula: see text] Br, I and [Formula: see text], 2, 3, 4) and the compounds formed in the PbO–SiO2 system. Standard formation enthalpy [Formula: see text], entropy [Formula: see text], heat capacity [Formula: see text] and temperature dependencies [Formula: see text] at temperatures T[Formula: see text][Formula: see text]k to 3000[Formula: see text]k were estimated. The standard estimation error of the thermodynamic properties of the compounds in the PbO–SiO2 system does not exceed 2% for all the estimated properties. For condensed halides, the standard estimation error was (1) [Formula: see text]% for enthalpy, (2) [Formula: see text]% for entropy, (3) [Formula: see text]% for heat capacity.

Thermodynamic Characteristics of a Series of Antimony Compounds: Standard Formation Enthalpy of Antimony Oxychloride SbOCl

2021 ◽  
pp. 109-115
Author(s):  
A.A. Gurov ◽  
A.N. Ozhogina ◽  
S.N. Solovyev
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Reference Values ◽  
Formation Enthalpy ◽  
Thermodynamic Characteristics ◽  
Dissolution Enthalpy ◽  
Formation Enthalpies ◽  
Margin Of Error ◽  
Measurement Results ◽  
Standard Formation Enthalpy

The present work opens a series of publications devoted to the description of the results of determination or clarification of the formation enthalpies of certain antimony compounds that are of significant applied interest to science and technology. The measurement results of enthalpy of interaction crystalline SbCl3 and water with formation of crystalline SbOCl are given. On the basis of the obtained and literature data, the value of standard formation enthalpy of the product of this interaction --- antimony oxychloride SbOCl at temperature 298.15 K is calculated. This value coincided with the reference values within the margin of error. An attempt was made to determine the dissolution enthalpy of SbCl3 in a two-molar aqueous solution of hydrochloric acid: the obtained approximate value of this characteristic was --30 ± 2 kJ/mol

ChemInform Abstract: Standard Formation Enthalpy of Some Crown-Ethers.

ChemInform ◽  
1992 ◽  
Vol 23 (51) ◽  
pp. no-no
Author(s):  
V. P. VASIL'EV ◽  
V. A. BORODIN ◽  
S. B. KOPNYSHEV
Keyword(s):  
Crown Ethers ◽  
Formation Enthalpy ◽  
Standard Formation Enthalpy

Thermochemistry in the system Cu–In–S at 723 K

1994 ◽  
Vol 9 (1) ◽  
pp. 125-131 ◽  
Author(s):  
H. Migge ◽  
J. Grzanna
Keyword(s):  
Thin Film ◽  
Free Energy ◽  
Solar Cells ◽  
Formation Enthalpy ◽  
Thin Film Solar Cells ◽  
Free Energies ◽  
Base Materials ◽  
Gibbs Triangle ◽  
Standard Formation Enthalpy ◽  
New Literature

A thermochemical analysis is performed in the system Cu-In-S at 723 K. Free energies of In6,S7, In417S583, “In2S3”, Cu951In49, and CuIn5S8 have been estimated, the numerical values (kJ/mol) of which are −1285, −97 780, −481.1, −31 680, and −1444. The free energy (kJ/mol) of CuInS2 is calculated from the relation G° = (-306.1 ± 54.4) + 0.5092T −1.397 10−5T2 −0.09468T In T + 268.2T−1, which is obtained from published assessed standard formation enthalpy and specific heat and entropy data. The free energy of the Cu-In melt is taken from very new literature. A consistent set of data is used for the calculation of a tentative Gibbs triangle as well as of the corresponding predominance area diagram. The Gibbs triangle is calculated with the program thermo, the algorithm of which is given. The results are in agreement with the results of published measurements, also for the equilibria which involve the melt. The compound CuInS2, one of the possible base materials for thin film solar cells, is shown to equilibrate with most of the compounds of the system. Predictions are made how to prepare CuInS2 from Cu-In alloys and H2S/H2 gas mixtures. However, more experiments are necessary to establish the data, the experiments, and/or the results of the calculations.

scholarly journals All Hands on Deck: Accelerating Ab Initio Thermochemistry via Wavefunction Approximations

2021 ◽  
Author(s):  
Sambit Kumar Das ◽  
Salini Senthil ◽  
Sabyasachi Chakraborty ◽  
Raghunathan Ramakrishnan
Keyword(s):  
Formation Enthalpy ◽  
Reference Value ◽  
Composite Model ◽  
Fine Tuning ◽  
Large Molecules ◽  
New Variant ◽  
Hands On ◽  
Standard Formation Enthalpy ◽  
Local Pair ◽  
The Individual

<div>We accelerate the G4(MP2) composite model by fine-tuning the individual steps using resolution-of-identity and domain‐based local pair‐natural orbitals. The new variant, G4(MP2)-XP, has a low prediction error when tested on 1694 benchmark molecules. To showcase the method's relevance for large molecules, we determine and present a new reference value for the standard formation enthalpy of buckminsterfullerene. We expect G4(MP2)-XP to become the <i>de facto</i> method for rapid and accurate production of thermochemistry big data.</div>

Standard Formation Enthalpy of Na2O–ZnO–P2O5 Series Glasses

2018 ◽  
Vol 1 (1-2) ◽  
pp. 43-51 ◽  
Author(s):  
Refka Oueslati-Omrani ◽  
Ismail Khattech ◽  
Mohamed Jemal
Keyword(s):  
Formation Enthalpy ◽  
Standard Formation Enthalpy

QUANTUM-CHEMICAL PREDICTION OF FORMATION ENTHALPY OF CYCLOALKANE

2010 ◽  
Vol 09 (supp01) ◽  
pp. 155-166
Author(s):  
XIN HONG ◽  
JING SHI
Keyword(s):  
Density Functional Theory ◽  
Quantum Chemical ◽  
Density Functional ◽  
Formation Enthalpy ◽  
Experimental Accuracy ◽  
Dft Methods ◽  
Functional Theory ◽  
Standard Formation Enthalpy

Based on the s-homodesmotic model and the seven different density functional theory (DFT) methods, we calculate standard formation enthalpy of cycloalkane of up to 10 carbons. Among the 21 different combinations, the scheme using MPWB1K method and working reactions when s = 2 achieves the experimental accuracy with RMSD of 8.49 kJ/mol. Also, credibility of this scheme is proved by discussion on influence from different aspects.

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