Search

Single crystals of bis(thiocyanato) cobalt(II) di thiourea [Co(NCS) 2 (N 2 H 4 CS) 2 ]; BTCT were grown from an aqueous solution using slow evaporation technique for the first time. Interestingly, Co 2+ ion present in the crystalline compound connects two N atoms of thiocyanate and four S atoms of thiourea ligands. The bridging thiourea ligands link Co ions into a one dimensional polymeric chain along [1 0 0] direction. Single crystal XRD shows that the BTCT crystal belongs to triclinic system with the space group P 1 ¯ . BTCT single crystals were subjected to FT-IR, Laser Raman, UV–vis, CHNS, TG-DTA and DSC studies. The optical study shows that the UV cut-off wavelength of BTCT in ethanol–water mixed solvent is about 310 nm. The thermal analysis of BTCT reveals that the sample is thermally stable up to 196.01 °C. The VSM study shows that Co 2+ in BTCT possesses higher coercivity (32.414 μCi) and retentivity (654.62E-6 emu/g) than Mn 2+ of [Hg(N 2 H 4 CS) 4 Mn(SCN) 4 ]; TMTM. [ABSTRACT FROM AUTHOR]

Swift Heavy Ion beam irradiation is capable of inducing a variety of modifications on the properties of thin films by high energy deposition. The Nb 2 O 5 thin films deposited by spray pyrolysis technique were then irradiated with 200 MeV Ag15+ ions at fluence ranging from 5 × 1011 to 1 × 1013 ions/cm2. The thickness of the deposited film was 308 nm and the irradiated area was 1x1 cm2. The XRD pattern of the pristine film confirmed the tetragonal structure of Nb 2 O 5. Upon irradiation, peak intensity decreased significantly and some peaks vanished due to irradiation induced defects. The subtle Raman peaks around 960, 223, and 126 cm−1 corresponds to edge shared octahedra, T 2u mode and Nb–Nb vibration respectively. After irradiation, complete suppression of vibration modes was observed except for 1 × 1012 fluence. For the 1 × 1012 ions/cm2 fluence, Raman modes reappear with increased intensity due to irradiation induced recrystallization. Optical transmittance spectra showed a decreased trend as fluence increased due to the formation of optically absorbing centers. Both the direct and indirect band gaps showed a systematic red shift. The pristine AFM image revealed agglomeration of particles while a network like structure was observed after irradiation. Results of transport properties studied for both pristine and irradiated films at room temperature by Hall effect are also presented. • Nb 2 O 5 film retained its tetragonal structure even after irradiation. • Increased Raman intensity for 1 × 1012 ions/cm2 fluence indicates irradiation induced recrystallization. • Red shift was observed in both the direct and indirect band gaps. • AFM revealed unique porous network morphology of Nb 2 O 5. • Maximum conductivity observed for 1 × 1012 ions/cm2 fluence by domination of band gap reduction over grain size. [ABSTRACT FROM AUTHOR]