Synthesis, characterizations and photo-physical properties of novel lanthanum(III) complexes

Abstract

A series of novel complexes of La(III) with substituted pyrazolines and mixed ligand complexes with these pyrazolines and thio-ligands have been synthesized and characterized by elemental analysis, molecular weight measurement, Fourier transform infra-red, 1 H and 13 C NMR spectroscopy. The particle/crystallite sizes were confirmed by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopic techniques. Optical characterizations have been performed by electronic absorption and fluorescence emission spectroscopies in order to investigate their luminescence behaviour, which reveals fairly good quantum yield and fluorescence life time for some of the complexes. Thermal analyses such as thermogravimetric and differential thermal analysis indicate that these complexes are thermally stable at high temperature. Investigations pertaining to solid-state optical absorption spectra and photoelectron yield spectroscopy reveal that upon thermal annealing beyond 300°C, these compounds form dark-brown to black semiconducting materials with an optical band gap between 1.9 and 2.3 eV. Abbreviations: La-PyH : La-HPY = [La(C 15 H 12 N 2 OH) 2 (H 2 O)Cl]; La-PyH-dtc = [La(C 15 H 12 N 2 OH)(C 5 H 10 NS 2)(2H 2 O)Cl]; La-OCPy-xan: [La(C 15 H 12 N 2 OOCH 3)(C 2 H 5 OCS 2)(2H 2 O)Cl] ARTICLE HISTORY

Development and Investigation of Lanthanum Sulfadiazine with Calcium Stearate and Epoxidised Soyabean Oil as Complex Thermal Stabilizers for Stabilizing Poly(vinyl chloride)

“…These characteristic peaks still exist after the formation of LaSD, indicating that there is no reaction between La 3+ and NH 2 . Moreover, an infrared characteristic peak is added at 418.4 cm −1 after the formation of lanthanum salt, which is attributed to the La-N characteristic peaks [30]. So, it can be proved that LaSD has been successfully synthesized.…”

Photo-physical properties of lanthanides doped O-bridged conducting indole oligomer

“…The presence of the NeH peak showing the noninvolvement of eNH group which is also supported by FTIR spectra. The presence of aromatic protons was confirmed by the presence of multiplet in the range d 7e8 ppm [37]. Peaks present at d 7.23e7.25 and 6.54e6.56 ppm indicate the existence of the CeH bond of the 2nd and 3rd position of the fivemembered ring [38].…”

Synthesis, spectroscopic characterization, density functional, thermal studies, and molecular docking simulation of rare earth element complexes

“…All the complexes were prepared by a general method. [ 24 ] The ethanolic solution of lanthanum(III) chloride was prepared and added to hot dimethylformamide (DMF) solutions of the ligands in 1:1 molar ratio. The solution was refluxed on a water bath for about 5 h, and the refluxing was continued for about 3 h. The resulting solutions were concentrated and kept overnight.…”

“…The complexes separated were filtered, washed successively with the ethanol and ether, and dried in the vacuum. [ 24 ]…”

“…In addition, certain complexes also undergo optoelectronic properties including an estimate of their optical band distance and energy for the highest occupied (HOMO) and the lowest unoccupied (LUMO) molecular orbitals to explore its potential for use with optoelectronic devices. [24] These findings led to investigate further the synthesis and reactivity of Schiff base ligands-supported organolanthanide complexes. [25] In this correspondence, preparation, and characterization studies on the Schiff base ligands and their REE complexes were reported.…”