1. Institute of Telecommunications, Radioelectronics and Electronic Engineering, Lviv Polytechnic National University, Bandery 12, 79046 Lviv, Ukraine
2. Scientific Research Company "Carat", Stryjska 202, 79031 Lviv, Ukraine
3. Institute of Physical and Theoretical Chemistry, Technical University Braunschweig, Hans-Sommer-Str. 10, D-38106 Braunschweig, Germany