Low-temperature structure of V₆O₁₃

Abstract

The structure of the transition metal oxide V6O13, a potential cathode material in lithium-polymer batteries, has been studied at 95 K using single-crystal X-ray diffraction (XRD). A phase transition has been determined by differential scanning calorimetry (DSC) measurements to occur at 153 K, with a heat of transition of -1.98 kJ mol(-1). In this low-temperature phase, the V and O atoms move by up to 0.21 A out of the mirror plane they occupy in the room-temperature structure. It is concluded that the earlier reported space group P2(1)/a [Kawada et al. (1978). Acta Cryst. B34, 1037-1039] is incorrect and that a more appropriate choice of space group is Pc.

Aqueous citrato-oxovanadate(iv) precursor solutions for VO2: synthesis, spectroscopic investigation and thermal analysis

“…29 Note that the decavanadate is subjected to acid-base equilibria (eqn (1)) with pK a1 , pK a2 and pK a3 equal to 1.9, 4.2 and 6.6, respectively. 29 The decavanadate species, present in the solution with a pH value of 6, are dominated by the presence of HV 10 ). Additionally, a signal at −535.7 ppm is observed in the 51 V-NMR spectrum.…”

“…S1 and S3: Fourier transform infra-red spectra; Tables S2 and S4: band assignments of the main vibrations of the Fourier transform infra-red spectra. See DOI: 10.1039/c4dt01346h…”

Studies towards a mechanistic insight into the activation of n-octane using vanadium supported on alkaline earth metal hydroxyapatites

“…XRD diffractograms were recorded from room temperature at an interval of 50 • C up to 600 • C. The sample was cooled to room temperature from 600 • C with an interval of 50 • C. Quantitative analysis of the phases present in the catalyst during the in situ XRD studies was done by using X'pert PAN analytical software. The crystallographic information files that were used to refine the phases present in the catalysts were obtained from literature [19][20][21][22][23][24].…”

Local environment dependentGGA+Umethod for accurate thermochemistry of transition metal compounds

“…The low temperature phase of V 6 O 13 is used in formation enthalpy calculations while room temperature phase is used for the voltage predictions. 83 The only mixed-valence compound we used in U prediction is Co 3 O 4 , because we could not find the experimental enthalpy for the marginally stable Co 3+ bearing oxide Co 2 O 3 . In addition, BaNi 4+ O 3 is the only ternary compound included in our U prediction calculations, since we…”