Titre du document / Document title
The crystal structure of kastningite (Mn, Fe, Mg) (H
2O)
4[Al
2(OH)
2(H
2O)
2(PO
4)
2].2 H
2O : a new hydroxyl aquated orthophosphate hydrate mineral
Auteur(s) / Author(s)
ADIWIDJAJA G.
(1) ;
FRIESE K.
(2) ;
KLASKA K.-H.
(1) ;
SCHLÜTER J.
(1) ;
Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)
(1) Universität Hamburg, Mineralogisch-Petrographisches Institut, Grindelallee 48, 20146 Hamburg, ALLEMAGNE
(2) Universidad del Pais Vasco, Facultad de Ciencias, Departamento de Fisica de la Materia Condensada, Apdo. 644, 48080 Bilbao, ESPAGNE
Résumé / Abstract
The crystal structure of kastningite, a new mineral from Waidhaus, Bavaria, Germany, has been determined. Ideal formula from X-ray structure analysis is Mn(H
2O)
4[Al
2(OH)
2(H
2O)
2(PO
4)
2].2 H
2O. Lattice parameters are a = 10.205(1) Å, b = 10.504(1) Å, c = 7.010(1) Å, α = 90.38(1)°, β = 110.10(1)°, γ = 71.82(1)° (space group P1, Z = 2). Kastningite is isostructural to stewartite Mn(H
2O)
4 .[Fe
3-2(OH)
2(H
2O)
2(PO
4)
2].2 H
2O. Chains of corner sharing octahedra run in the [102] direction. Within the chain, octahedra of composition [Al(OH)2(O
P)
2(H
2O)
2]
3- alternate with others of composition [Al(OH)
2(O
P)
4]
7- (with O
P designating oxygen atoms which form part of a phosphate group). The resulting chain composition is [Al(O
P)
3(OH)(H
2O)]
4- Symmetry equivalent chains are bridged by [PO
4]
3- tetrahedra and sheets parallel to {010} of composition [Al
2(OH)2(H
2O)2(PO
4)
2]
2- are formed. [Mn(H
2O)
4(O
P)
2]
2- octahedra link these sheets in the direction of [010] thus resulting in a three dimensional structure. The structure is further held together by a complex system of hydrogen bonds. Chains of corner-sharing octahedra which are further connected to [PO
4]
3- tetrahedra are a common feature within other aquated orthophosphate hydrate minerals. Yet there are differences with respect to the number of symmetrically equivalent octahedra within the chain, their composition as well as to the way they are connected to the tetrahedra. A brief comparison of kastningite to these other minerals is given.
Revue / Journal Title
Zeitschrift für Kristallographie
ISSN 0044-2968
CODEN ZEKRDZ
Source / Source
1999, vol. 214, n
o8, pp. 465-468 (14 ref.)
Langue / Language
Anglais
Revue : Allemand
Editeur / Publisher
Oldenbourg, München, ALLEMAGNE
(1921)
(Revue)
Mots-clés anglais / English Keywords
crystal structure ;
phosphates ;
structural formula ;
Bavaria Germany ;
new minerals ;
X-ray diffraction ;
unit cell ;
cell dimensions ;
atomic packing ;
coordination ;
hydrogen bond ;
interatomic bond ;
Germany ;
Central Europe ;
Europe ;
Mots-clés français / French Keywords
Structure cristalline ;
Phosphate ;
Formule structurale ;
Bavière ;
Minéral nouveau ;
Diffraction RX ;
Maille élémentaire ;
Constante réticulaire ;
Empilement atome ;
Coordinence ;
Liaison hydrogène ;
Liaison interatomique ;
Kastningite ;
Allemagne ;
Europe Centrale ;
Europe ;
Mots-clés espagnols / Spanish Keywords
Estructura cristalina ;
Fosfato ;
Baviera ;
Mineral nuevo ;
Difracción RX ;
Celdilla cristalina ;
Constante reticular ;
Estructura átomo ;
Coordinancia ;
Enlace hidrógeno ;
Enlace interatómico ;
Alemania ;
Europa central ;
Europa ;
Localisation / Location
INIST-CNRS, Cote INIST : 915, 35400008612930.0060
Nº notice refdoc (ud4) : 1912161
