TY - JOUR

T1 - Crystal structure and comparative crystal chemistry of romanorlovite

AU - Zubkova, Natalia V.

AU - Krivovichev, S. V.

AU - Pekov, I. V.

AU - Zolotarev, A. A.

AU - Pushcharovsky, D. Y.

AU - Sidorov, E. G.

PY - 2016/1/1

Y1 - 2016/1/1

N2 - Crystal structure and crystal chemical features of a new, discovered in fumaroles of the Tolbachik volcano (Kamchatka) copper and potassium hydroxychloride - romanorlovite, with the simplified formula K 11 Cu 9 Cl 25 (OH) 4 ∙2H 2 O (Z = 4), are reported. The mineral is tetragonal, I4/mmm, a = 17.5538(19), c = 15.8620(17) Å, V = 4887.7(9) Å 3 . The structure was determined using single-crystal XRD data and refined to R = 5.49 % for 769 unique reflections with I > 2s(I). The structure is based on two main blocks built by Cu 2+ -centere polyhedra. The first one includes chains consisting of edge-sharing CuCl 4 (OH) 2 octahedra. In the chain a fragment built by four edge-sharing Cu(1)-centered octahedral could be distinguished whereas Cu(2)-centered octahedra are connected with this fragment from both upper and lower sides. The second structural block consists of isolated Cu 6 Cl 18 clusters built by Cu(3)-centered tetragonal pyramids and Cu(4)-centered distorted tetrahedra. In a core of the cluster Cu2+ and Pb2+ cations statistically replacing each other in the same site are located. Two these basic structural blocks are connected via distorted ACl 6 octahedra (A = Cu, K) forming pseudo-framework. K+ cations are located in the voids and channels of the pseudo-framework. Romanorlovite has the crystal-chemical formula K 24 (K,Pb) 16 (K,Cu,□) 8 Cu 28 (□,Cu) 16 (□,Cu,Pb) 2 Cl 92 $ (Cl,9) 8 (9,Cl) 8 (OH) 16 ∙8H 2 O (Z = 1). Various defects revealed in its structure are discussed.

AB - Crystal structure and crystal chemical features of a new, discovered in fumaroles of the Tolbachik volcano (Kamchatka) copper and potassium hydroxychloride - romanorlovite, with the simplified formula K 11 Cu 9 Cl 25 (OH) 4 ∙2H 2 O (Z = 4), are reported. The mineral is tetragonal, I4/mmm, a = 17.5538(19), c = 15.8620(17) Å, V = 4887.7(9) Å 3 . The structure was determined using single-crystal XRD data and refined to R = 5.49 % for 769 unique reflections with I > 2s(I). The structure is based on two main blocks built by Cu 2+ -centere polyhedra. The first one includes chains consisting of edge-sharing CuCl 4 (OH) 2 octahedra. In the chain a fragment built by four edge-sharing Cu(1)-centered octahedral could be distinguished whereas Cu(2)-centered octahedra are connected with this fragment from both upper and lower sides. The second structural block consists of isolated Cu 6 Cl 18 clusters built by Cu(3)-centered tetragonal pyramids and Cu(4)-centered distorted tetrahedra. In a core of the cluster Cu2+ and Pb2+ cations statistically replacing each other in the same site are located. Two these basic structural blocks are connected via distorted ACl 6 octahedra (A = Cu, K) forming pseudo-framework. K+ cations are located in the voids and channels of the pseudo-framework. Romanorlovite has the crystal-chemical formula K 24 (K,Pb) 16 (K,Cu,□) 8 Cu 28 (□,Cu) 16 (□,Cu,Pb) 2 Cl 92 $ (Cl,9) 8 (9,Cl) 8 (OH) 16 ∙8H 2 O (Z = 1). Various defects revealed in its structure are discussed.

KW - Copper hydroxychloride

KW - Crystal structure

KW - Fumarole

KW - Kamchatka

KW - New mineral

KW - Romanorlovite

KW - Structure defect

KW - Tolbachik volcano

UR - http://www.scopus.com/inward/record.url?scp=85041932102&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:85041932102

VL - 145

SP - 92

EP - 102

JO - ЗАПИСКИ РОССИЙСКОГО МИНЕРАЛОГИЧЕСКОГО ОБЩЕСТВА

JF - ЗАПИСКИ РОССИЙСКОГО МИНЕРАЛОГИЧЕСКОГО ОБЩЕСТВА

SN - 0869-6055

IS - 4

ER -