Lower valence fluorides of chromium. 2. The phase potassium chromium fluoride (K0.43-0.59CrF3)

High-temperature DTA studies of AxMF3 compounds (, Rb, Cs; , Cr; and )

“…The A x CrF 3 compounds were analyzed for K, Rb, Cs, and Cr; %F was taken by difference. %K, %Rb, %Cs, %Cr, and %F were in good agreement with calculated values [11,12].…”

“…Products were analyzed optically by stereoscopic and polarized microscopy and further characterized by X-ray powder diffraction (25 1C) and magnetic measurements from 4.2 to 300 K [8][9][10][11][12]. Chemical analyses of K, Rb, Cs, V, and F in the A x VF 3 compounds were in agreement with calculated values [7][8][9][10].…”

“…The compounds studied were previously characterized in this laboratory [7][8][9][10][11][12]. Every precaution was taken to ensure that the samples were oxygen free.…”

“…The lower-valence fluorides of vanadium, A x VF 3 , and chromium, A x CrF 3 (where A ¼ K, Rb, or Cs), were first reported elsewhere [1][2][3][4][5][6], but their X-ray structures at 25 1C, along with those of Tl x VF 3 , were studied intensively in this laboratory [7][8][9][10][11][12]. Most of these materials demonstrate small crystal distortions and/or modulated structures, which are the consequence of concomitant ordering or displacive transitions that set in above 25 1C when they are cooled from higher temperatures.…”

“…The b phase of K x CrF 3 consists of three distinct structures at 25 1C [12]. The first, at the lowest range of x, is an aristotype structure corresponding to BaTa 2 O 6 ðD 1 6h -P6=mmmÞ.…”