INDEX geometric parameters

Table 2. Symbols for Topological Indexes, Geometrical Parameters, and Hydrogen Bonding Parameter and Their Definitions...

A theoretical study at a HF/3-21G level of stationary structures in view of modeling the kinetic and thermodynamic controls by solvent effects was carried out by Andres and coworkers [294], The reaction mechanism for the addition of azide anion to methyl 2,3-dideaoxy-2,3-epimino-oeL-eiythrofuranoside, methyl 2,3-anhydro-a-L-ciythrofuranoside and methyl 2,3-anhydro-P-L-eiythrofuranoside were investigated. The reaction mechanism presents alternative pathways (with two saddle points of index 1) which act in a kinetically competitive way. The results indicate that the inclusion of solvent effects changes the order of stability of products and saddle points. From the structural point of view, the solvent affects the energy of the saddles but not their geometric parameters. Other stationary points geometries are also stable. 

Table 4 HF/6-31G calculated geometric parameters (a-c In A sum of the bond angle at P In deg) and aromaticity Indexes (Bird Index)...

In many cases it is possible to simplify these equations because only relatively few components of P are significant, either because of the synunetry or the electronic structure of the molecules. When it is possible to reduce the number of distinct significant components to at most two, then it is often possible to extract the ratio of these components and geometric information directly from the observed values of the susceptibility. In these cases the values assumed for the interfacial refractive index and the role of the contributions from the bulk can make a dramatic difference to the derived geometric parameters [21-27]. 

The geometrical parameters of the low-index A1 surfaces are summarised in Table 2. As can be seen from the table, the surface structures of Al(lll) and... 

In this work, we discuss the results of DFT calculations for some all-metal clusters with the general formula MAI/ at a validated level of theory and numerical precision and compute a number of accepted properties to describe aromaticity, such as 17, geometrical parameters, the DI, and the NICS indexes. Hereby, we pursue the evaluation of DFT calculations and reactivity descriptors to explain and assess aromaticity in the anionic all-metal clusters derived from the Al/- unit. We determine the effect of different charges and multiplicities on the geometry of Al/(n = —2, —1,0,1) and calculate the structures of new complexes MA14" where M = (Li+, Na+, K+), (Be+2, Mg+2, Ca+2), (Sc+3, Ti+4), and (B+3, Al+3, Ga+3). In order to compare the DFT reactivity descriptors, we compute other parameters (NICS and DIs) and study periodic trends. 

An additional connectivity index (°%), the geometrical parameter Nrot, and the atomic correction term Ngj, were used along with 1%v in the final fit. Weight factors of 100/Cps(exp)... 

Table 4.1. Experimental heat capacities Cps of solid polymers at room temperature (298K) in J/(mole K), the geometrical parameter Nrot and the atomic correction index NSi used in the correlation, and the fitted values of Cps, for 95 polymers. The connectivity indices and 1xv. 

Table 4.3. Experimental change ACp of the heat capacity at the glass transition in J/(mole K), the geometrical parameter NBBrol used in the correlation, and the fitted values of ACp, for 89 polymers. The connectivity index 1%v, which is also used in the correlation, is listed in Table 2.2. The alternative set of values listed in Table 2.3 is used for the silicon-containing polymers. The 33 ACp(exp) values listed in parentheses are those for which there is a question mark in parentheses ( ) for the appropriate number of "mobile beads" in the tabulations [3,34],... 

Geometrical parameters, such as molecular shape parameters," sterimol descriptors, volume, bulk parameters, " " and 3D Wiener index,"" have been developed and used in SARs. Such parameters are derived from the relative distances of atoms in the 3D Euclidean space. We give below some examples of QSARs using 3D descriptors. 

Method Classification Particle propaty Equiv. diameter or related geometric parameter Type of quantity (index, index for nanoparticles) Size and concentration range (conservative) Comments... 

In our further considerations we start from the assumption that the geometrical and physical parameters of the photodetector are already defined. Geometrical parameters include the area and the thickness of the active region, i.e., its total volume. Physical parameters are the detector material properties. These include optical properties (complex refractive index, determined by the material type and composition), and electrical ones (donor and acceptor concentration, i.e., the concentrations of majority and minority carriers at a given temperature). 

Material index (M). The performance of material is defined by P = / (F, G, M), where F is the functional requirement, G is geometrical parameter and M is material properties. The performance for all F and G is maximized by maximizing material properties which is called Material Index (merit index or material factor). 

The constant C2 incorporates only the terms appearing in Eqs. (4.8) and (4.12) which are dependent only on the geometrical parameters of the melt flow indexer... 

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