Magnesium Aluminum Spinel (MgAl2O4)

Publisher Summary Magnesium aluminum spinel (MgAl2O4) is a face-centered cubic material, the prototype for the spinel structural family, which includes binary oxides, sulfides, and selenides. The space group is Fd3m, unit cell length is 0.8084 nm, and the unit cell has eight formula units. The positions of the ions in the unit cell have been determined by both X-ray and neutron diffraction techniques. There is an inverse spinel structure, wherein the aluminum ions occupy both Td and D3d sites, and the magnesium ions occupy some of the D3d sites. The occurrence of the normal, inverse, or in-between structure depends on the ionic size, method of preparation, and composition. Natural magnesium aluminum spinel has the normal spinel structure; however synthetic forms of spinel prepared at high temperature have the inverse structure. The composition of magnesium aluminum spinel varies from near stoichiometric to highly alumina-rich. Optical-quality spinel can be synthetically made with a variety of techniques including: growth using the Czochralski method, the gradient furnace technique, hot pressing of powder, press forging, flame fusion, and fusion casting.

[1]  W. Ho.  High-Temperature Dielectric Properties of Polycrystalline Ceramics , 1988 .

[2]  G. W. Clark,et al.  Multiple‐Tube Flame Fusion Burner for the Growth of Oxide Single Crystals , 1962 .

[3]  F. Waldner,et al.  A direct determination of cation disorder in MgAl2O4 spinel by ESR , 1972 .

[4]  P. Tarte,et al.  Infrared studies of spinels—III. The normal II-III spinels , 1971 .

[5]  K. Wickersheim,et al.  Optical Properties of Synthetic Spinel , 1960 .

[6]  R. Weeks,et al.  Photoelectric effects in magnesium aluminum spinel , 1980 .

[7]  H. Saalfeld,et al.  Kationenverteilung und Strukturbeziehungen in Mg-Al-Spinellen , 1958 .

[8]  K. Vedam,et al.  Piezo- and thermo-optic behavior of spinel (MgAl2O4) , 1975 .

[9]  W. Stręk,et al.  Optical properties of Cr3+ in MgAl2O4 spinel , 1988 .

[10]  W J Tropf,et al.  Infrared transmission properties of sapphire, spinel, yttria, and ALON as a function of temperature and frequency. , 1988, Applied optics.

[11]  Donald W. Roy,et al.  Polycrystalline MgAl2O4 (Spinel) For Use As Windows And Domes From 0.3 To 6.0 Micrometers , 1983, Other Conferences.

[12]  G. A. Slack,et al.  FeAl 2 O 4 - MgAl 2 O 4 : Growth and Some Thermal, Optical, and Magnetic Properties of Mixed Single Crystals , 1964 .

[13]  The parabolic axicon: author's reply to comments. , 1975, Applied optics.

[14]  F. Campbell,et al.  The spatial resolving power of the human retina with oblique incidence. , 1960, Journal of the Optical Society of America.

[15]  J. H. Crawford,et al.  Optical spectra of MgAl2O4 crystals exposed to ionizing radiation , 1982 .

[16]  P. Fischer.  Neutronenbeugungsuntersuchung der Strukturen von MgAl-20-4- und ZnAl-20-4-Spinellen, in Abhängigkeit von der Vorgeschichte , 1967 .

[17]  Chen,et al.  Optical transitions in neutron-irradiated MgAl2O , 1988, Physical review. B, Condensed matter.

[18]  C. C. Wang,et al.  Dielectric and Optical Properties of Stoichiometric Magnesium Aluminate Spinel Single Crystals , 1971 .

[19]  T. M. Hartnett,et al.  Optical And Mechanical Properties Of Highly Transparent Spinel And ALON Domes , 1984, Optics & Photonics.

[20]  F. Laves,et al.  Ordnung / Unordnung und Ultrarotabsorption III. Die Systeme MgAl2O4–Al2O3 und MgAl2O4–LiAl5O8 , 1961 .

[21]  W. White,et al.  Interpretation of the vibrational spectra of spinels , 1967 .

[22]  J. Mccauley,et al.  Growth of nearly stoichiometric MgAl2O4 spinel single crystals by a gradient furnace technique , 1972 .

[23]  Summers,et al.  Luminescence and photoconductivity in magnesium aluminum spinel. , 1985, Physical review. B, Condensed matter.

[24]  Michael E. Thomas,et al.  A Computer Code For Modeling Optical Properties Of Window Materials , 1989, Defense, Security, and Sensing.

[25]  J. H. Crawford,et al.  Effects of γ‐irradiation upon the optical behavior of spinel , 1977 .

[26]  J. S. Reed.  Optical Absorption Spectra of Cr3+ in MgO·Al2O3‐MgO·3.5Al2O3 Spinels , 1971 .

[27]  B. Cockayne,et al.  The vertical pulling of MgAl2O4 single crystals , 1967 .

[28]  C. C. Wang.  Growth and Characterization of Spinel Single Crystals for Substrate Use in Integrated Electronics , 1969 .

[29]  C. Angeletti,et al.  Structure and catalytic activity of CoχMg1–χAl2O4 spinel solid solutions. Part 1.—Cation distribution of Co2+ ions , 1977 .

[30]  J. Heaney,et al.  Spinel (AI(2)O(3):MgO): refractive-index variations and lack of stoichiometry in evaporated films. , 1981, Applied optics.

[31]  J. H. Crawford,et al.  Radiation damage in MgAl/sub 2/O/sub 4/ , 1980 .

[32]  A. Alper,et al.  The System MgO–MgAl2O4 , 1962 .

[33]  A. L. Frisillo,et al.  Lattice vibrations of MgAl2O4 spinel , 1973 .

[34]  J. Vickerman,et al.  Solid state properties of copper containing spinel solid solutions (CuxMg1–xAl2O4) , 1977 .

[35]  S. I. Boldish,et al.  Transverse and longitudinal optic frequencies of spinel MgAl2O4 , 1978 .

[36]  G. Bacon.  A neutron‐diffraction study of magnesium aluminium oxide , 1952 .