X-a method

Junqing Li, X-a Method and Its Application in Quantum Chemistry, Anhui Keji Publ. House, Hefei, Peoples Republic of China, 1984. 

L. Kover, Proceedings of the First International Workshop on DV-X.a Method DV-X.u 96, with Special Emphasis on Inner-Shell Physics and Chemistry. Proceedings of a conference held 2-3 September 1996, in the ATOMKI, Debrecen, Hungary, in Adv. Quantum Chem., Vol. 29, Academic Press, San Diego, 1997. 

Hirohiko Adachi, Introduction to Quantum Chemistry forMaterials Approach from DV-X.-a Method, Sankyo Shuppan, Tokyo, 1991. 

A wide range of theoretical methods has been applied to the study of the structure of small metal clusters. The extremes are represented on the one hand by semi-empirical molecular orbital (Extended Huckel) (8 ) and valence bond methods (Diatomics-In-Molecules) ( ) and on the other hand by rigorous initio calculations with large basis sets and extensive configuration interaction (Cl) (10). A number of approaches lying between these two extremes have been employed Including the X-a method (11), approximate molecular orbital methods such as CNDO (12) and PRDDO (13) and Hartree-Fock initio molecular orbital theory with moderate Cl. 

The DV X a-method has been first proposed and formulated more than 25 years ago by Ellis and Painter at Northwestern University. This method allows to calculate relatively large systems with medium accuracy. However the knowledge of energy eigenvalues, electron distributions, effective charges or overlap populations etc. are a valid tool for physical and chemical interpretations. 

Ab initio SCF energy calculations were used to determine the structures of several carbohydrates [46-47]. The PCILO method [48] was applied to carbohydrates [49]. The X-a method [50] can be parametrized for metal atoms so that calculations on sugar-metal complexes are possible (for example, the studies on sugar-metal interactions by Tajmir-Riahi [51]). 

M. Case, Electronic structure calculations using the X-a method. Ann. Rev. Phys. Chem., 33 (1982) 151. 

We make further comparison with the SW-Xa results where the multiplet was estimated in the same way as in the present work. Component energies for the Ijt — 2rt transition obtained by the present DV-Xa method and the SW-X a method are shown in Table II. 

Masson (19) studied the equilibrium between the discrete anions and fi ee oxygen ions on the basis of the statistical thermodynamics. He proposed a model in which fi ee ojqrgen ions dissociated during pofymeriTation of discrete anions. We also succeeded in explaining the equilibrium between fi ee oxygen ions and discrete anions in molten slags based on the electronic states calculated with the DV-X a method (26). 

Adachi, R Introduction to Quantum Materials Chemistry Approach with DV-X a Method , Sankyo Syuttpan, Tokyo, 1991,26,50 [in Japanese]. 

Lessel, U.F. and Briem, H. (2000) Flexsim-X a method for the detection of molecules with similar biological activity. J. Chem. Inf. Comput. Sci., 40, 246-253. 

The explicit consideration of lone pairs is a significant part of the so-called X-a method (see. for example, Kaufman, 1973). 

Waber, J. T. and Averill, F. W. 1974. Molecular orbitals of PtF6 and El 10 F6 calculated by the self-consistent multiple scattering X a method. J Chem Phys 60, 4460-4470. 

Silver ions yield an intensely purple complex with sodium 2-(8-hydroxyquinolin-5-ylazo)benzoate (29) in tartrate buffer at pH 5.2 to 6.1 X 525 nm, e 365(X) . A method involving a large multiplication factor consists of decomposition of ferrocyanide complex ions [Fe(CN)6] with Ag(I) to give [Ag(CN)2] . In the presence of crystal violet (CV,... 

The valence level M.O. diagram for C, as calculated by the MS X-a method is presented in figure 2. Bond lengths used to generate the structure were those of Liithi and Almlof. ... 

You have a polynomial. Equation (6.20), that you must solve for the one unknown X (a method for solving polynomials like Equation (6.20) is given on page 55). You begin with knowledge of . Compute the value x that solves Equation (6.20). Then substitute x into Equations (6.19) to give the distribution function (p, p. P ) ... 

Masner, P., Slama, K., Zd arek, J., and Landa, V. (1970), Natural and synthetic materials with insect hormone activity. X. A method of sexually spread insect sterility, J. Econ. Entomol. 63, 706-710. 

Value of the stirface potential X a Method to be applied for the caiculation of the interaction of two spherical double layers ... 

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