Third-order NLO properties of the DMF solutions of 3-D network and 2-D layered organic-metal polymers with (4, 4) grid units

3-D polymer {[Cd(bbbm)(SO4)(H2O)2]CH3OH}n (1) containing 60-membered metallocyclic ring systems and bridging SO42-, 2-D polymers {Ni(bbbm)2(H2O)2}(NO3)2 · 2CH3OH · 6H2O}n (2) and {[Co(bbbm)2(H2O)2](NO3)2 · 2CH3OH · 6H2O}n (3) with (4, 4) grid units have been synthesized. The third-order nonlinear optical (NLO) properties are determined in DMF solution and the results show that the DMF solution of 2 possesses both the large third-order NLO absorptive and strong refractive behaviors, and 3's shows large NLO absorptive effect and weak NLO refractive behavior.