The novel benzo-15-crown-5 (B15-C-5), dibenzo-18-crown-6 (DB18-C-6) complexes: [Na (B15-C-5)]_2[Pt(SCN)_6] (1) and [Na(DB18-C-6)]_2[Pt(SCN) _6] (2) have been synthesized and characterized by elemental analysis, IR spectroscopy and X-ray diffraction analysis. Complex 1 belongs to monoclinic, space group P2_1/c with cell dimensions: a = 1.0974(5) nm, b = 1.5187(7) nm, c = 1.3632(6) nm, β = 96.407(7)°, V = 2.2568(18) nm~3, Z = 2, D_(calcd) = 1.746 g/cm~3, F(000) = 1184, R_1 = 0.0357, wR_2 = 0.0868. Complex 2 is in triclinic crystal system, space group P1-bar with cell dimensions: a = 1.2500(3) nm, b = 1.2825(3) nm, c = 1. 9342(4) nm, α = 106.82(3)°, β = 102.51(3)°, γ = 103.04(3)°, V = 2. 7562 nm~3, Z = 2, D_(calcd) = 1.579 g/cm~3, F(000) = 1316, R_1 = 0.0364, wR_2 = 0.0771. Each complex shows a two-dimensional network structure of [Na(B15-C-5)]~+ or [Na(DB18-C-6)]~+ cations and [Pt(SCN)_6]~(2-) anions bridged by Na-N interactions between adjacent [Na(B15-C-5)]~+ or [Na(DB18-C-6)]~+ and [Pt(SCN)_6]~(2-) units.

Key words: CROWN ETHER COMPOUNDS, PLATINUM COMPLEX, RETICULAR FORMATION, ELEMENTAL ANALYSIS, IR