One disorder out of two orders: Synthesis and crystal structures of cation-ordered PbNaF 2 NO 3 , anion-ordered Pb 2 OFNO 3 , and continuous disordered (Pb, Na) 2 (O,F) 2-δ NO 3 solid solution with Sillén-derived structures

The first bismuth borate oxyiodide, Bi4BO7I: commensurate or incommensurate?

“…Eight 1 4 -occupied oxygen sites are defined at 0.25 < t < 0.75, two 1 2 -occupied oxygen sites are defined at 0.25 < t < 0.5 and two 1 2 -occupied oxygen sites are defined at 0.5 < t < 0.75. In principle, this is rather similar to the overall tenfold coordination of nitrogen in MBiO 2 NO 3 (M = Ca and Pb; Ziegler et al, 2004), as well as PbLnO 2 NO 3 (Dill et al, 2006) and (Na,Pb) 2 (O,F) 2 NO 3 (Charkin et al, 2017), where it was The observed Fourier map of the electron-density distribution in the layers (x 1 , x 4 ), (x 2 , x 4 ) and (x 3 , x 4 ) for Bi 4 BO 7 I at the position of the (a) Bi, (b) I/B, (c) O1, (d) O2, (e) O3 and (f) O4 atoms. Contour intervals are 5 e A ˚-3 for bismuth and 1 e A ˚À3 for the B, I and O1-O4 atoms.…”

“…Eight 1 4 -occupied oxygen sites are defined at 0.25 < t < 0.75, two 1 2 -occupied oxygen sites are defined at 0.25 < t < 0.5 and two 1 2 -occupied oxygen sites are defined at 0.5 < t < 0.75. In principle, this is rather similar to the overall tenfold coordination of nitrogen in MBiO 2 NO 3 (M = Ca and Pb; Ziegler et al, 2004), as well as PbLnO 2 NO 3 (Dill et al, 2006) and (Na,Pb) 2 (O,F) 2 NO 3 (Charkin et al, 2017), where it was research papers Acta Cryst. (2020).…”

Structural, thermal, and IR studies of β-[Nd2O2](CrO4), an unexpected analog of a slag phase [Ba2F2](S6+O3S2−)

“…Several attempts to resolve the disorder in the doubled unit cells as reported in [4,11] remained unsuccessful. The methods and software utilized were the same [21] as used previously for the structure determination of related layered lead compounds [12,23].…”