Nanoscale hemispheres in novel mixed-valent uranyl chromate(V,VI), (C3NH10)10[(UO2)13(Cr12(5+)O42)(Cr(6+)O4)6(H2O)6](H2O)6

Oleg I Siidra; Evgeny V Nazarchuk; Anatoly A Petrunin; Roman A Kayukov; Sergey V Krivovichev

doi:10.1021/ic301288r

Nanoscale hemispheres in novel mixed-valent uranyl chromate(V,VI), (C3NH10)10[(UO2)13(Cr12(5+)O42)(Cr(6+)O4)6(H2O)6](H2O)6

Inorg Chem. 2012 Sep 3;51(17):9162-4. doi: 10.1021/ic301288r. Epub 2012 Aug 20.

Authors

Oleg I Siidra¹, Evgeny V Nazarchuk, Anatoly A Petrunin, Roman A Kayukov, Sergey V Krivovichev

Affiliation

¹ Department of Crystallography, St. Petersburg State University, University emb. 7/9, St. Petersburg, 199034 Russia. siidra@mail.ru

PMID: 22906619
DOI: 10.1021/ic301288r

Abstract

The structure of a novel mixed-valent chromium uranyl compound, (C(3)NH(10))(10)[(UO(2))(13)(Cr(12)(5+)O(42))(Cr(6+)O(4))(6)(H(2)O)(6)](H(2)O)(6) (1), obtained by the combination of a hydrothermal method and evaporation from aqueous solutions with isopropylammonium, contains uranyl chromate hemispheres with lateral dimensions of 18.9 × 18.5 Å(2) and a height of about 8 Å. The hemispheres are centered by a UO(8) hexagonal bipyramid surrounded by six dimers of Cr(5+)O(5) square pyramids, UO(7) pentagonal bipyramids, and Cr(6+)O(4) tetrahedra. The hemispheres are linked into two-dimensional layers so that two adjacent hemispheres are oriented in opposite directions relative to the plane of the layer. From a topological point of view, the hemispheres have the formula U(21)Cr(23) and can be considered as derivatives of nanospherical cluster U(26)Cr(36) composed of three-, four-, and five-membered rings.