The crystal of complex Eu(a-NMA)_3(a-HNMA)Phen (NMA = naphthoate; HNMA = naphthoic acid and phen= 1,10-phenanthroline) belongs to triclinic, PI space group, with cell parameters a = 1.2401(3) nm, b = 1.3056(3) nm, c = l.6500(3) nm, a =73.01(3)°, β= 82.44(3)°, 3w; w, w, w = 62.07(3)°, V = 2.2572(8) nm3, Z =2, D_c= 1.496 g/cm~3, F(000) = 1026, R = 0.0517. The complex is a binuclear molecule with the four bridged carboxylate groups of the naphthoate bonded to the two europium ions. Each ion is linked to five oxygen atoms from the bridging carboxylates, two oxygen atoms from a chelating carboxylate group and two nitrogen atoms of a phenanthroline, forming a nine coordinated distorted tricapped trigonal prism. The intramolecular it- it interaction between naphthoate and phenantnroline planes may stabilize the coordination geometry. The result of fluorescence spectra indicates that the title complex has excellent luminescence properties.

Key words: EUROPIUM COMPLEX, CRYSTAL STRUCTURE, FLUORIMETRIC ANALYSIS, NAPHTHALENECARBOXYLIC ACID P, PHENANTHROLINE, CHARACTERISTICS OF LUMINESCENCE