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A detailed study of the elastic scattering of electrons and positrons from two C3v symmetrical molecules viz ammonia and phosphine molecules is presented. The partial wave phase shift analysis method with complex optical potential consisting of static, exchange, polarization and an imaginary absorption potentials has been used. In contrast to the previously used similar approaches, the present method is quite different in the sense that we have obtained the required static potential in an analytical form using correctly represented Gaussian molecular wave functions for NH3 and PH3 in our calculations. The differential, integrated, momentum transfer, absorption and total cross sections are calculated and reported in the incident electron and positron energy range of 10–500 eV. In order to test the applicability of our approach, the present results are compared with the available previous measurements and theoretical calculations and a good agreement is found.

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The present paper reports electron impact total inelastic and ionization cross section for silicon, germanium, and tin tetrahalides at energies varying from ionization threshold of the target to 5000 eV. These cross section data over a wide energy domain are very essential to understand the physico-chemical processes involved in various environments such as plasma modeling, semiconductor etching, atmospheric sciences, biological sciences, and radiation physics. However, the cross section data on the above mentioned molecules are scarce. In the present article, we report the computation of total inelastic cross section using spherical complex optical potential formalism and the estimation of ionization cross section through a semi-empirical method. The present ionization cross section result obtained for SiCl4 shows excellent agreement with previous measurements, while other molecules have not yet been investigated experimentally. Present results show more consistent behaviour than previous theoretical estimates. Besides cross sections, we have also studied the correlation of maximum ionization cross section with the square root of the ratio of polarizability to ionization potential for the molecules with known polarizabilities. A linear relation is observed between these quantities. This correlation is used to obtain approximate polarizability volumes for SiBr4, SiI4, GeCl4, GeBr4, and GeI4 molecules.

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