We present a general methodology for evaluating structure factors defining the orientation dependence of tunneling ionization rates of molecules, which is a key process in strong-field physics. The method is implemented at the Hartree-Fock level of electronic structure theory and is based on an integralequation approach to the weak-field asymptotic theory of tunneling ionization, which expresses the structure factor in terms of an integral involving the ionizing orbital and a known analytical function. The evaluation of the required integrals is done by three-dimensional quadrature which allows calculations using conventional quantum chemistry software packages. This extends the applications of the weak-field asymptotic theory to polyatomic molecules of almost arbitrary size. The method is tested by comparison with previous results and illustrated by calculating structure factors for the two degenerate highest occupied molecular orbitals (HOMOs) of benzene and for the HOMO and HOMO-1 of naphthalene
The effect of various regimes of plasma irradiation in the "Plasma focus" device on the surface structure of vanadium has been studied. It is established that at the plasma power density values of 108 – 1010 W/cm2 there are pores, microcracks and gas bubbles in the structure of material. In addition, as a result of the plasma action, the ejection of individual pieces of material from the irradiated vanadium surface was observed.