The reaction of CuI and L in the molar

All commercially available chemicals ETC-1002 of reagent grade and used as received without further purification. The ligands of L1 and L2 were prepared according to the procedures reported previously [12]. Elemental analyses of C, H, and N were taken on a Perkin-Elmer 240C elemental analyzer at the analysis center of Nanjing University. Infrared spectra (IR) were recorded on a Bruker Vector22 FT-IR spectrophotometer by using KBr pellets. Thermogravimetric analyses (TGA) were performed on a simultaneous SDT 2960 thermal analyzer under nitrogen with a heating rate of 10 °C min−1. The solid-state CD (KCl pellets) measurements were in a Circular Dichroism Spectrometer of J-810. The second-order non-linear optical (NLO) intensity was estimated by measuring a powder sample of 80–150 mm diameter in the form of a pellet relative to urea. A pulsed Qswitched Nd:YAG laser at a wavelength of 1064 nm was used to generate an second-harmonic-generation signal (SHG) from powder samples. The backscattered SHG light was collected by a spherical concave mirror and passed through a filter pioneer community transmits only 532 nm radiation. The electric hysteresis loops were recorded on a Ferroelectric Tester Precision Premier II made by Radiant Technologies, Inc. The luminescence spectra for the powdered solid samples were measured at room temperature on an Aminco Bowman Series2 spectrofluorometer with a xenon arc lamp as the light source. In the measurements of emission and excitation spectra the pass width is 5 nm. All the measurements were carried out under the same experimental conditions.