Sublimation energies

The W—W bond energy should be about one-sixth of the sublimation energy (note Section III-IB), and there are various schemes for estimating electronegativities, of which Mulliken s [151,152] is perhaps the most fundamental. 

As an example of a multilayer system we reproduce, in Fig. 3, experimental TPD spectra of Cs/Ru(0001) [34,35] and theoretical spectra [36] calculated from Eq. (4) with 6, T) calculated by the transfer matrix method with M = 6 on a hexagonal lattice. In the lattice gas Hamiltonian we have short-ranged repulsions in the first layer to reproduce the (V X a/3) and p 2 x 2) structures in addition to a long-ranged mean field repulsion. Second and third layers have attractive interactions to account for condensation in layer-by-layer growth. The calculations not only successfully account for the gross features of the TPD spectra but also explain a subtle feature of delayed desorption between third and second layers. As well, the lattice gas parameters obtained by this fit reproduce the bulk sublimation energy of cesium in the third layer. 

The group oxidation state of +5 is too high to allow the formation of simple ionic salts even for Nb and Ta, and in lower oxidation states the higher sublimation energies of these heavier metals, coupled with their ease of oxidation, again militates against the formation of simple salts of the oxoacids. As a consequence the only simple oxoanion salts are the sulfates of vanadium in the oxidation states +3 and +2. These can be crystallized from aqueous solutions as hydrates and are both strongly... 

Palladium forms clusters of these types far less readily than nickel and platinum, unless they are stabilized by o-donor ligands such as phosphines. This may be due to the lower energy of Pd-Pd bonds as reflected in the sublimation energies, 427, 354 and 565 kJ mol for Ni, Pd and Pt. 

The atoms of any metal adhere together to form a crystal because of the forces of attraction between them to remove an atom from the surface requires a definite amount of work, characteristic of the metal this is called the sublimation energy. ... 

Intermolecular potential functions have been fitted to various experimental data, such as second virial coefficients, viscosities, and sublimation energy. The use of data from dense systems involves the additional assumption of the additivity of pair interactions. The viscosity seems to be more sensitive to the shape of the potential than the second virial coefficient hence data from that source are particularly valuable. These questions are discussed in full by Hirschfelder, Curtiss, and Bird17 whose recommended potentials based primarily on viscosity data are given in the tables of this section. 

The packing energy of an organic crystal can be easily calculated by a lattice sum over pairwise interactions. The potential parameters for these calculations are summarized in Table 15. The packing energy is usually a quite accurate estimate of the crystal sublimation energy. 

LRmax maximum tolerable leak rate of a plant LS sublimation energy of water... 

However, the obscure choice of frequencies in the visible and UV regions in the original calculations may have been guided by a desire to fit experimental heats. In fact, the Debye rotational and translational crystal frequencies relate to sublimation energies of the lattice, and, together with internal molecular vibrations, can be used to calculate thermodynamic functions (16). An indirect connection between maximum lattice frequencies (vm) and heats of formation may hold because the former is inversely related to interatomic dimensions (see Section IV,D,1) ... 

Several computations of the total surface energy (per unit area) Us start from the experimental value of the sublimation energy, Ls, of the crystal. When it is remembered that the intensity of interatomic forces frequently is derived from thisZ,S) the direct use of the experimental data does not appear to be a serious drawback. On the other hand, this approach does not differentiate between different crystal faces and can give only an averaged value for all of these. 

Fig. S-7. Fonnation of standard gaseous ion, S gio), from surfa(% atom of a semiconductor of single element S S = surface ion h = hole SC = semiconductor, CB = conduction band VB = valence band sublimation energy of the surface ion vl> s outer potential.

Fig. 4-16. Energy levels of metal ion and electron in an ionic electrode of metal ion transfer 4Cjn i = sublimation energy of solid metal /m" = ionization energy of gaseous metal atoms > >s = outer potential of electrolyte solution E s electrode potential (absolute electrode potential).

The energies required by these processes are composed of the sublimation energy of the metal (Es) and the dissociation energy of the gaseous molecule (fEjf). 

In the Langmuir free-evaporation method, the sample is suspended freely in a vacuum system with no container sunounding it. As very low levels of vapour pressure can be measured it has advantages over the Knudsen method where the lower limit is about 10" atm. (Kubaschewski et al. 1993). It is therefore more usefril in materials with high sublimation energies and therefore inherently low vapour pressiues. It has a further advantages in that there is no container with which to react, but there are more significant problems associated with temperature measurement. 

Malta and co-workers [41] conclude that stability of the molecules investigated is explained partially in terms of the energy that is necessary to disrupt the encasing network of these H-H bond paths. These interactions must be ubiquitous, and their stabilization energies contribute to the sublimation energies of hydrocarbon molecular crystals. 

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