A novel unexpected luminescent quarternary coordination polymer {Sm3(C8H4O4)4(C12N2H8)2(NO3)}n with three high asymmetrical central Sm fragments by hydrothermal assembly

A novel chain-like luminescent samarium coordination polymer {Sm3(C8H4O4)4(C12N2H8)2(NO3)}n (C8H4O4 = phthalate, C12N2H8 = 1,10-phenanthroline) has been assembled by hydrothermal process. The title complex crystallizes in the monoclinic system, space group P2(1)/c, with lattice parameters a = 22.56(3) Å, b = 11.155(15) Å, c = 20.32(3) Å, β = 96.70(2)°, V = 5078(12) Å3, F(000) = 2964, GOF = 0.857, R1 = 0.0358, wR2 = 0.0597, Z = 4. Samarium ions exhibit different coordination modes from each other and lead to the unexpected high asymmetrical structure. To our knowledge, it is the first example of lanthanide coordination polymers comprising the three asymmetrical central Sm3+ fragments. The photophysical properties have been studied with excitation and emission spectra.