Reversible crystal to crystal transformation of a hydrogen-bonded polymer to another in a solid-gas reaction along with morphology change: nano-particles to nano-rods conversion

Abstract

Crystal to crystal transformation along with morphology change of a new lanthanum(III) nitrate hydrogen bonded polymer with ligands 4,4′-bipyridine (4,4′-bipy), [La(4,4′-bipy)(H₂O)₂(NO₃)₄]·(4,4′-Hbipy) (1) to [La(4,4′-Hbipy)(NO₃)₅]·(4,4′-Hbipy) (2), has been reported. Structures of 1 and 2 were determined and their thermal properties as well as solid state UV/vis spectra have been reported and compared. Nano-particles of compound 1 were synthesized by a sonochemical method and characterized by scanning electron microscopy (SEM), X-ray powder diffraction, IR spectroscopy and elemental analyses. The SEM studies show that the nano-particles of compound 1 under transformation change to nano-rods of compound 2.