Weitere Verbindungen des Ba17Ln16Zn8Pt4O57- Typs mit Ln = Dy, Ho, Er, Y / More Compounds of the Ba17Ln16Zn8Pt4O57 Type with Ln = Dy, Ho, Er, Y

1997 ◽  
Vol 52 (9) ◽  
pp. 1067-1071 ◽  
Author(s):  
O. Sfreddo ◽  
Hk. Müller-Buschbaum

Abstract Single crystals of Ba17Dy16Zn8Pt4O57 (I), Ba17Ho16Zn8Pt4O57 (II), Ba17Er16Zn8Pt4O57 (III) and Ba17YZn8Pt4O57 (IV) have been prepared by high temperature reactions using platinum crucibles. X-ray investigations led to tetragonal symmetry, space group C54h - I4/m, (I) - (IV): a = 22.905(1), 22.840(1), 22.795(1), 22.848(1) Å and c = 5.728(1), 5.722(1), 5.700(1), 5.709(1) Å,Z = 2. The crystal structure is characterized by small square, medium-sized quadrangular and large rectangular tunnels, which are filled by oxygen, barium and zinc. The polyhedra network is discussed with respect to the network of compounds of the Ba13Dy8Zn4Pt4O37 type.

1994 ◽  
Vol 49 (3) ◽  
pp. 355-359 ◽  
Author(s):  
F.-D. Martin ◽  
H. Müller-Buschbaum

Abstract Single crystals of KBaCuV2O7Cl have been prepared by a flux technique and investigated by X-ray analysis. The compound crystallizes with tetragonal symmetry, space group C24v-P4 bm, a = 8.8581, c = 5.4711 Å, Z = 2. The crystal structure shows Cu2+ within a one sided strongly distorted CuO4Cl2 octahedron. The copper ion is shifted towards the nearer Cl- neighbour to form a CuO4Cl square pyramid. Two VO4 tetrahedra are connected to give stretched V2O7 double tetrahedra, and linked in planes via the oxygen corners of the CuO4Cl pyramids. The crystal structure and the structure of the complex BaO8Cl2 polyhedron are discussed.


1997 ◽  
Vol 52 (5) ◽  
pp. 553-556 ◽  
Author(s):  
O. Sfreddo ◽  
Hk. Müller-Buschbaum

Abstract Single crystals of Ba13Dy8Zn4Pt4O37 have been prepared by reaction of mixtures of BaCO3, ZnO and DyO3 at temperatures up to 1225 °C using platinum crucibles. X-ray investigations led to a new crystal structure with tetragonal symmetry, space group C4h5-I4/m, a = 18.659(7), c = 5.734(2) Å, Z = 2. The structure is characterized by PtO6 and BaO6 octahedra as well as by tetragonal ZnO5 pyramids and single capped trigonal prisms of oxygen around dysprosium. The remaining barium positions show coordination numbers of nine and ten. The crystal structure has large ∞1[(PtDy4O)6)4] polyhedra tunnels. Considering the ∞1[Ln4O16]20- polyhedra groups some parts of the structure show similarities to BaZnLn2O5, Ba5Zn4Ln8O21 and Ba2Ln2ZnPtO8.


1995 ◽  
Vol 50 (2) ◽  
pp. 252-256 ◽  
Author(s):  
H. Szillat ◽  
Hk. Müller-Buschbaum

Single crystals of AgKCu3Mo4O16 have been prepared by crystallization from melts and investigated by X-ray diffractometer techniques. This compound crystallizes with monoclinic symmetry, space group C2h5 - P21/c, a = 5.056(1), b = 14.546(4), c = 19.858(9) Å, β = 86.64(5)°, Z = 4. The crystal structure of AgKCu3Mo4O16 is closely related to K2Cu3Mo4O16 showing ribbons of edge-sharing CuO6 and AgO7 polyhedra. The ribbons are linked by tetrahedrally coordinated molybdenum and K2O10 groups. Another kind of MoO4 tetrahedra occupies the cavities inside the ribbons. The crystal structure and the coordination of silver, copper, potassium and molybdenum by oxygen are discussed with respect to K2Cu3Mo4O16.


1995 ◽  
Vol 50 (4) ◽  
pp. 585-588 ◽  
Author(s):  
S. Frenzen ◽  
Hk. Müller-Buschbaum

Single crystals of Ba9Ru3.2Mn5.8O27 have been prepared by flux techniques. X-ray four circle diffractometer measurements led to trigonal (rhombohedral) symmetry, space group D53d - R3̄̄̄m , a = 5.7043(5), c = 21.255(4) Å , Z = 1. This phase is isotypic to BaRuO3. The crystal structure and the occupation of the M3O12 triple octahedra by ruthenium and manganese are discussed with respect to other oxides containing M3O12 groups in an ordered and disordered way.


1995 ◽  
Vol 50 (6) ◽  
pp. 879-883 ◽  
Author(s):  
H. Szillat ◽  
Hk. Müller-Buschbaum

Single crystals of Ag0.5Cu3V0,5Mo2,5O12 have been prepared by crystallization from melts and investigated by X -ray methods. They crystallize with triclinic symmetry, space group Ci1 -P 1̄ , a = 6.797(6), b = 8.575(6), c = 9.897(7) Å, α = 103.47(6), β = 103.69(6), γ = 101.48(6)° and Z = 4. The crystal structure is characterized by chains of edge-sharing CuO6 octahedra and CuO5 pyramids. Special features of this com pound are the square planar surrounding of Ag+ by O2− and a statistical distribution of molybdenum and vanadium at one point position.


1994 ◽  
Vol 49 (9) ◽  
pp. 1277-1281 ◽  
Author(s):  
Ch. Rabbow ◽  
Hk. Müller-Buschbaum

High temperature reactions of BaCO3/MnO/Er2O3 (3:1:1) led to single crystals of Ba3ErMn2O9. The product shows the structure of the hexagonal precious metal oxides Ba3LnRu2O9, but crystallizes with orthorhombic symmetry, space group C122v-Cmc21, a = 5.823 Å, b - 10.099 Å, c = 14.409 Å; Z = 4. The crystal structure is characterized by ErO6 octahedra, Mn2O9 face shared double octahedra and Ba2+ within cuboctahedral and anticuboctahedral coordination by O2-, respectively. In contrast to precious metal oxides the Mn-Mn distances inside the Mn2O9 double octahedra are elongated


1997 ◽  
Vol 52 (4) ◽  
pp. 453-456 ◽  
Author(s):  
B. Mertens ◽  
Hk. Müller-Buschbaum

Abstract Single crystals of (I) Rb4Cd(VO)(V2O7)2Cl und Tl4Cd(VO)(V2O7)2Cl have been prepared by flux techniques. The compounds were examined by X-ray analysis. They crystallize with tetragonal symmetry, space group C14-P4 with (I): a=9.142(1); c=5.525(1), (II): a=9.150(1), c=5.405(1) A, Z = 4. Both compound belong to the K4CuV5O15Cl-Type. V (l) forms V2O7 double tetrahedra, connected by square V(2)O5 pyramids and CdO4Cl2 octahedra. The short V(2)-O distance indicates a vanadyl group.


1998 ◽  
Vol 53 (3) ◽  
pp. 287-290 ◽  
Author(s):  
B. Wedel ◽  
L. Wulff ◽  
Hk. Müller-Buschbaum

Abstract Single crystals of Pb2TeO5 have been prepared by flux techniques. X-ray investigations showed a new crystal structure with monoclinic symmetry, space group C4S -Cc, a = 13.099(3), b = 5.714(1), c = 7.520(2) Å, β = 123,80(3)°, Z = 4. Pb2TeO5 is characterized by 1∞[TeO5] chains of octahedra isolated from each other and incorporated into an edge, corner and face connected frame of PbO7 polyhedra. Possible positions of the lone pair of electrons of Pb2+ are estimated by calculations of Coulomb terms of lattice energy.


1996 ◽  
Vol 51 (3) ◽  
pp. 447-449 ◽  
Author(s):  
O. Sedello ◽  
Hk. Müller-Buschbaum

Abstract Single crystals of (Cu,Mn)3.66Mo3O12 have been prepared in sealed copper tubes. X-ray investiga­tions lead to orthorhombic symmetry, space group D2h16-Pnma, a = 5.1541(9), b = 10.788(2), c = 18.114(3)) Å , Z = 4. (Cu,Mn)3.66Mo3O12 is iso­typic to NaCo2.31Mo3O12 and (Cu,Co)3.75Mo3O12 with split positions for two of the metals.


1996 ◽  
Vol 51 (3) ◽  
pp. 450-452 ◽  

Abstract Single crystals of (Cu,Mn)UMo3O12 have been prepared in sealed copper tubes. X-ray investigations lead to hexagonal symmetry, space group C6h2-P63/m a = 9.7895 (13), c = 6.202(1) Å , z = 2. (Cu,Mn)UMo3O12 is isotypic to CdThMo3O12. Calculations of the Coulomb terms of lattice energy with respect to different oxidation states of copper, molybdenum and uranium and the previously described pair of isotypic compounds of CdThMo3O12 to Na2ThRe6O24 are discussed.


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