The crystal and mol. structure of [Sc(NO3)3(OH2)3].18-crown-6 (I) was determine from single crystal x-ray diffraction. I crystd. in the orthorhombic space group Pna21 with Z = 4, a 15.300(3), b 10.879(3), c 14.052(3) ? R = 0.0739 for 975 reflections. The Sc3+ ion is 9-coordinate, being bonded to 3 bidentate nitrate groups and to 3 H2O mols. in a capped square antiprism. There are 6 H atoms in 3 coordinated H2O mols., 3 of them are bonded to 3 O atoms in the above crown ether ring; the rest of them are bonded to the lower layer crown ether ring. I forms a multilayer sandwich structure. The preparation of I is given.

Key words: CRYSTAL STRUCTURE DETERMINATION, CROWN ETHER COMPOUNDS, NITRIC ACID, CHEMICAL BONDS, AQUO COMPLEX, COORDINATE CHEMISTRY, SANDWICH COMPOUNDS, SCANDIUM COMPLEX