In analogy with graphane and fluorographene the model for the compounds h-AB – C, where А and В atoms occupy the sites of the flat hexagonal lattice and С atoms, connected with А and В atoms, are placed by the opposite sides of the АВ-list is proposed. Numerical estimations are fulfilled for the h-A3B5 – C4 compounds, where А, В and С are the atoms from the same row of the Periodic Table. Analytical results are obtained for the electronic spectrum, quantum capacitance, local defect states, force constants and characteristics phonon friquences.