Abstract
The a and c unit cell parameters of M(OH)2, brucite-like structures with M=Mg, Ni, Co, Fe, Mn, Cd, and Ca, are considered in relation to M-O distances taken as the sum of the ionic radii, MVI and OIV. The a parameters are related to (M-O) by flattening of the octahedral coordination groups, with a flattening angle α=97.4±0.4°. The c parameters are divided into the octahedral layer thickness, h(oct), and the interlayer spacing h(inter). The latter is related to the (O-H) distances, which decrease as (M-O) increases. Infrared v(O-H) stretching frequencies vary with (M-O) in the same manner as h(inter) varies with (M-O). The values of v(O-H) decrease as h(inter) decreases and the atomic weight of the cations increases. The results are consistent with previous data for cation-substituted talcs. It is suggested that the M2+ ions associated with the O2− ions modify the reduced mass of the O-H vibrations so that v(O-H) decreases with increasing mass of M.
Similar content being viewed by others
References
Aminoff G (1919) Über die Krystallstruktur des Pyrochroits. Geol För Förh Stockholm 41:407–430
Aminoff G (1921) Über die Struktur des Magnesiumhydroxydes. Z Kristallogr 56:506–509
Brindley GW, Bish DL, Wan H-M (1979) Compositions, structures, and properties of nickel-containing minerals in the kerolite-pimelite series. Am Mineral 64:615–625
Busing WR, Levy HA (1957) Neutron diffraction study of calcium hydroxide. J Chem Phys 26:563–568
De Haan YM (1965) Kristalbouw en roosterenergie van laagstructuren van het type cadmium hydroxyde. PhD Thesis, Tech Hogeschool Delft, Netherlands
De Haan YM (1969) Structure refinements, thermal motion and Madelung constants of CdI2- and Cd(OH)2-type structures. Nat Bur Stand (US), Spec Publ No 301, 233–236
Lin J-C, Guggenheim S (1983) The crystal structure of a Li,Be-rich brittle mica: a dioctahedral-trioctahedral intermediate. Am Mineral 68:130–142
Oswald HR, Asper R (1977) Bivalent metal hydroxides, in Lieth RMA (ed), “Preparation and Crystal Growth of Materials with Layered Structures,” Reidel Pub Co, Holland, pp 77–140
Petch HE (1961) The hydrogen positions in portlandite, Ca(OH)2, as indicated by the electron distribution. Acta Crystallogr 14:950–957
Peterson RC, Hill RJ, Gibbs GV (1979) A molecular-orbital study of distortions in the layer structures brucite, gibbsite, and serpentine. Can Mineral 17:703–711
Shannon RD (1974) Systematic studies of interatomic distances in oxides, in Strens RTG (ed) “Physics and Chemistry of Minerals and Rocks,” Wiley Interscience Publns, New York, pp 403–431
Szytula A, Murasik A, Balanda M (1971) Neutron diffraction study of Ni(OH)2. Phys Status Solidi 43:125–128
Toraya H (1981) Distortions of octahedra and octahedral sheets in 1 M micas and the relation to their stability. Z Kristallogr 157:173–190
Wilkins RWT, Ito J (1967) Infrared study of some synthetic talcs. Am Mineral 52:1649–1661
Zigan F, Rothbauer R (1967) Neutronbeugungsmessungen am Brucit. Neues Jahrb Mineral Monatsh 137–143
Author information
Authors and Affiliations
Additional information
Deceased October 23, 1983
Rights and permissions
About this article
Cite this article
Brindley, G.W., Kao, CC. Structural and IR relations among brucite-like divalent metal hydroxides. Phys Chem Minerals 10, 187–191 (1984). https://doi.org/10.1007/BF00311476
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00311476