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Atomic heat theory

There is, however, a fatal objection to the theory of Boltzmann. At very low temperatures the oscillations will be small, and should conform to the theory. But the atomic heats, instead of approaching the limit 5 955 at low temperatures, diminish very rapidly, and in the case of diamond the specific heat is already inappreciable at the temperature of liquid air. A new point of view is therefore called for, and it is a priori very probable that this will consist of a replacement of the hypothesis of Equipartition of Energy adopted by Boltzmann. This supposition has been verified, and the new law of partition of energy derived... [Pg.519]

According to Joule s law ( 9), the molecular heat of a compound is the sum of the atomic heats of its components, and since this holds good even when the atomic heats are irregular, i.e., not equal to 6 4, it seems that the heat content of a solid resides in its atoms, and not in the molecular complexes as such. This agrees with Einstein s theory. Hence the molecular heat of a compound should be calculable by means of the formula ... [Pg.530]

The atomic properties satisfy the necessary physical requirement of paralleling the transferability of their charge distributions - atoms that look the same in two molecules contribute identical amounts to all properties in both molecules, including field-induced properties. Thus the atoms of theory recover the experimentally measurable contributions to the volume, heats of formation, electric polarizability, and magnetic susceptibility in those cases where the group contributions are found to be transferable, as well as additive additive [4], The additivity of the atomic properties coupled with the observation that their transferability parallels the transferability of the atom s physical form are unique to QTAIM and are essential for a theory of atoms in molecules that purports to explain the observations of experimental chemistry. [Pg.207]

Daltons scientific contributions were not limited to atomic theory. He also developed the concept of partial vapor pressure and did important work in the area of heat theory. Upon his death in 1844 in his longtime home of Manchester, England, 40,000 people attended the funeral of this unassuming teacher and researcher. [Pg.40]

The important conclusions, therefore, to be drawn from the Debye theory are that at low temperatures the atomic heat capacity of an element should be proportional to T, and that it should become zero at the absolute zero of temperature. In order for equation (17.4) to hold, it is necessary that the temperature should be less than about 9/10 this means that for most... [Pg.124]

Further work on similar types of cells has been carried out, in which not only is use made of the Nernst Theorem but likewise of the Einstein theory of atomic heat of solids (as modified by Nernst and Lmdemann) This will be taken up after we have discussed Planck s Quantum Theory of radiation and Einstein s application of it to the heat capacity of solids (Vol. Ill)... [Pg.382]

The older theory can offer no explanation for the other much more important deviation from equation (11) which occurs without exception at low temperatures. It is at the lowest temperatures, when the oscillations about the mean position are the smallest, and should consequently best agree with theory, that the atomic heats of compounds fall to very low values. [Pg.58]

Basis Sets Correlation Consistent Sets Benchmark Studies on Small Molecules Complete Active Space Self-consistent Field (CASSCF) Second-order Perturbation Theory (CASPT2) Configuration Interaction Configuration Interaction PCI-X and Applications Core-Valence Correlation Effects Coupled-cbister Theory Density Functional Applications Density Functional Theory (DFT), Har-tree-Fock (HF), and the Self-consistent Field Density Functional Theory Applications to Transition Metal Problems Electronic Structure of Meted and Mixed Nonstoi-chiometric Clusters G2 Theory Gradient Theory Heats of Formation Hybrid Methods Metal Complexes Relativistic Effective Core Potential Techniques for Molecules Containing Very Heavy Atoms Relativistic Theory and Applications Semiempiriced Methetds Transition Metals Surface Chemi-ced Bond Transition Meted Chemistry. [Pg.3093]

In statistical mechanics (e.g. the theory of specific heats of gases) a degree of freedom means an independent mode of absorbing energy by movement of atoms. Thus a mon-... [Pg.127]

Another theory of liquid-liquid explosion comes from Board et al. (1975). They noticed that when an initial disturbance, for example, at the vapor-liquid interface, causes a shock wave, some of the liquid is atomized, thus enhancing rapid heat transfer to the droplets. This action produces further expansion and atomization. When the droplets are heated to a temperature equal to the superheat temperature limit, rapid evaporation (flashing liquid) may cause an explosion. In fact, this theory resembles the theory of Reid (1979), except that only droplets, and not bulk liquid, have to be at the superheat temperature limit of atmospheric pressure (McDevitt et al. 1987). [Pg.160]


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See also in sourсe #XX -- [ Pg.32 ]




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