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Donald D Wagman

Bio: Donald D Wagman is an academic researcher from National Institute of Standards and Technology. The author has contributed to research in topics: Gibbs free energy & Standard enthalpy of formation. The author has an hindex of 12, co-authored 21 publications receiving 3744 citations.

Papers
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Book
01 Jan 1952
TL;DR: The Selected Values of Chemical Thermodynamic Properties as mentioned in this paper, published by the National Bureau of Standards (NBS) in 1952, is a seminal work in the field of thermodynamics.
Abstract: The theoretical framework of thermodynamics was well established by the time NBS was founded, and certain important applications, such as improving the efficiency of steam engines, had been demonstrated. However, the broad application of thermodynamics to the design and control of industrial processes had to await the accumulation and organization of a large amount of experimental data, as well as theoretical contributions from quantum mechanics and statistical mechanics. The appearance of Selected Values of Chemical Thermodynamic Properties [1] in 1952 marked a significant milestone in this process. This book represented the culmination of 20 years of work by Frederick D. Rossini and coworkers in evaluating and systematizing the data that had appeared in the world literature on thermochemistry. It tabulated accurate values of the thermodynamic properties of all inorganic and simple organic compounds that had been investigated in a format that allowed prediction of the outcome of many thousands of chemical reactions. Such calculations, which indicate whether a reaction will take place and, if so, the extent of reaction and amount of heat released or absorbed, are immensely important in research and engineering. Selected Values, which was often referred to simply as “Circular 500” after its NBS publication designation, presented recommended values of the enthalpy (heat) of formation, Gibbs energy of formation, entropy, and heat capacity of individual chemical compounds in different physical states (solid, liquid, gas, or aqueous solution). All values were reduced to standard state conditions, defined by parameters such as temperature (25 C) and pressure (one standard atmosphere). Since the laws of thermodynamics require that the change in properties such as energy and entropy cannot depend on the path followed in going from an initial to a final state—otherwise one could build a perpetual motion machine—the net change in thermodynamic properties in a chemical reaction can be calculated by addition and subtraction of the standard state values for the substances taking part in the reaction. This allows a simple prediction of whether the reaction will occur at all and, if it does, whether it will go to completion. In intermediate situations, one can obtain a quantitative measure of the extent of reaction from the equilibrium constant, which is easily calculated from the tabulated standard state values. Finally, most chemical changes involve either an absorption or release of heat, and the amount of this heat may be calculated from the same data. Thus Selected Values provided an extremely powerful tool for predicting the course of chemical reactions, a goal of chemists since the earliest days of the science. The book itself was 822 pages in length and covered about 5000 chemical species. It was divided into two parts, the first dealing with the thermodynamic properties in a particular physical state and the second with the change in properties in transitions between states (such as melting and vaporization). All data were internally consistent, in the sense that all physical and thermodynamic relations existing between different properties for the same substance, or the same property for different substances, were satisfied by the tabulated values. The table layout in Circular 500 became the norm for thermodynamic tabulations throughout the world. Fig. 1. Frederick D. Rossini.

1,460 citations

Book
01 Jun 1982
TL;DR: In this paper, a new collective edition of the "Selected values of Chemical Thermodynamic Properties," which was issued serially as National Bureau of Standards Technical Notes 270-1 (1965) to 270-8 (1981), was published.
Abstract: : Recommended values are provided for chemical thermodynamic properties of inorganic substances and for organic substances usually containing only one or two carbon atoms. Where available, values are given for the enthalpy of formation, Gibbs energy of formation, entropy, and heat capacity at 298.15 K (25 C), the enthalpy difference between 298.15 and 0 K and the enthalpy of formation at 0 K. All values are given in SI units and are for a standard state pressure of 100 000 pascal. This volume is a new collective edition of 'Selected Values of Chemical Thermodynamic Properties,' which was issued serially as National Bureau of Standards Technical Notes 270-1 (1965) to 270-8 (1981). Values are given for properties of gaseous, liquid and crystalline substances, for solutions in water, and for mixed aqueous and organic solutions. Values are not given for alloys or other solid solutions, fused salts or for substances of undefined composition. Compounds of the transuranium elements are not included. (Author)

1,337 citations

01 Jan 1968
TL;DR: In this paper, the Gibbs energy of formation, enthalpy, entropy and heat capacity for all inorganic substances and organic molecules containing not more than two carbon atoms are given.
Abstract: : The tables contain values where known of the enthalpy and Gibbs energy of formation, enthalpy, entropy and heat capacity at 298.15 K (25 C), and the enthalpy of formation at 0 K, for all inorganic substances and organic molecules containing not more than two carbon atoms. In some instances such as metal-organic compounds, data are given for substances in which each organic radical contains one or two carbon atoms. No values are given in these tables for metal alloys or other solid solutions, fused salts, or for substances of undefined chemical composition.

94 citations


Cited by
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Book ChapterDOI
TL;DR: The chapter reviews that the denaturation is a process in which the spatial arrangement of the polypeptide chains within the molecule is changed from that typical of the native protein to a more disordered arrangement.
Abstract: Publisher Summary This chapter explores that the changes that take place in the protein molecules during denaturation constitute one of the most interesting and complex classes of reactions that can be found either in nature or in the laboratory These reactions are important because of the information they can provide about the more intimate details of protein structure and function They are also significant because they challenge the chemist with a difficult area for the application of chemical principles The chapter reviews that the denaturation is a process in which the spatial arrangement of the polypeptide chains within the molecule is changed from that typical of the native protein to a more disordered arrangement The chapter also discusses the classification of protein structures: primary, secondary, and tertiary structures The primary structure is that expressed by the structural chemical formula and depends entirely on the chemical valence bonds that the classical organic chemist would write down for the protein molecule The secondary structure is the configuration of the polypeptide chain that results from the satisfaction of the hydrogen bonding potential between the peptide N-H and C=O groups The tertiary structure is the pattern according to which the secondary structures are packed together within the native protein molecule The term “denaturation” as used in this chapter is indented to include changes in both the secondary and tertiary structures

4,528 citations

Journal ArticleDOI
TL;DR: This article corrects the article on p. 100 in vol.
Abstract: [This corrects the article on p. 100 in vol. 41.].

3,345 citations

Journal ArticleDOI
TL;DR: This work focuses on the calculations of vibrational spectra, thermodynamic quantities, isotopic substitution effects, and force constants in a fully integrated program for the study of chemical reactions involving molecules, ions, and linear polymers using MOPAC.
Abstract: Before we start, we need a working definition for MOPAC. The following description has been used many times to describe MOPAC: MOPAC is a general-purpose, semiempirical molecular orbital program for the study of chemical reactions involving molecules, ions, and linear polymers. It implements the semiempirical Hamiltonians MNDO, AM 1, MINDO/3, and MNDOPM3, and combir_es the calculations of vibrational spectra, thermodynamic quantities, isotopic substitution effects, and force constants in a fully integrated program. Elements parameterized at the MNDO level include H, Li, Be, B, C, N, O, F, A1, Si, P, S, C1, Ge, Br, Sn, Hg, Pb, and I; at the PM3 level the elements H, C, N, O, F, A1, Si, P, S, C1, Br, and I are available. Within the electronic part of the calculation, molecular and localized orbitals, excited states up to sextets, chemical bond indices, charges, etc. are computed. Both intrinsic and dynamic reaction coordinates can be calculated. A transition-state location routine and two transition-state optimizing routines are available for studying chemical reactions.

2,422 citations

Journal ArticleDOI
TL;DR: A review of surface science studies of single crystal surfaces, but selected studies on powder and polycrystalline films are also incorporated in order to provide connecting points between surface sciences studies with the broader field of materials science of tin oxide as discussed by the authors.

2,232 citations