Lamda 750 spectrometer

Infrared spectra of the solid samples were recorded on a PerkinElmer Spectrum-One FT-IR spectrophotometer by making KBr pellets. Powder X-ray diffraction patterns were recorded using a Bruker powder X-ray diffractometer D2 phaser. ¹H-NMR spectra of complexes were recorded on a BRUKER Ascend-600 MHz NMR spectrometer using TMS as the internal standard. A PerkinElmer Lamda-750 spectrometer was used to record the solid-state UV-visible spectra by diffuse reflectance. Fluorescence emissions were measured in a Horiba Jobin Yvon Fluoromax-4 spectrofluorometer by taking definite amounts of solutions or definite amounts of solid samples and exciting at the required wavelength. Quantum yields were measured by taking definite amounts of solids and solutions and exciting at the required wavelength in a Horiba Jobin Yvon Fluoromax-4 spectrofluorometer by Petite integrating sphere method. The fluorescence emission (E_c) and the scatter (L_c) for the sample and blank (L_a and E_a) were recorded. From these spectral measurements (sample and blank), the quantum yields were calculated by using the equation φ = [(E_c − E_a)/(L_a − L_c)].

Thermogravimetric analysis and differential scanning calorimetry were performed simultaneously from room temperature to 600 °C using a TA Instruments Q600 SDT instrument with an air flow of 100 mL min^–1 at a heating rate of 5 °C min^–1. Fourier-transform infrared spectroscopy (FTIR) was carried out using a Bruker Tensor 27 infrared spectrometer with a diamond attenuated total reflectance (ATR) attachment. The data were collected in the wavenumber range from 520 to 4000 cm^–1 at room temperature. Diffuse reflectance spectra were obtained using a PerkinElmer Lamda 750 spectrometer with an integrating sphere detector in the wavelength range from 2500 to 220 nm. The powder samples were diluted to 10 wt% with dry BaSO₄. The diffuse reflectance spectra were converted into Kubelka–Munk (K–M) functions with the concentration corrections. Electron spin resonance (ESR) spectra were collected at room temperature using a JEOL JES-TE200 ESR spectrometer with a 100 kHz field modulation.