Anomalous behavior at the I2/a to Imab phase transition in SiO2-moganite: An analysis using hard-mode Raman spectroscopy

Abstract The silica polymorph moganite is commonly intergrown with quartz in microcrystalline silica varieties that are less than ~100 Ma in age. Synchrotron X-ray diffraction suggests that a displacive phase transition occurs when moganite is heated above ~570 K, with an increase in symmetry from I2/a to Imab. In the present study, we employed hard-mode Raman spectroscopy to confirm the existence of the α-β moganite transformation and to offer complementary insight into the transition mechanism. Our analysis of the displacement of the 501 Δcm-1 symmetric stretching-bending vibration (B3g mode) with changing temperature strongly supports the existence of a monoclinic-to-orthorhombic phase transition between 570 and 590 K. Between 593 and 723 K, however, the mode remained fixed at 496 Δcm-1. This behavior was repeated on cooling, but with a hysteresis of over 100 K. We offer three hypotheses that may explain this observation: (1) the intergrowth of nanoscale quartz lamellae within moganite may exert a strain that inhibits the transition; (2) the transition may exhibit a martensitic character marked by the co-existence of α- and β-moganite over a finite temperature interval; and (3) the α- and β-moganite transition may occur via an intermediate phase.

[1]  A. Nukui,et al.  Non‐integral phase in tridymite , 2008 .

[2]  Odgers,et al.  Laser Raman identification of silica phases comprising microtextural components of sinters , 2008 .

[3]  J. Krucnra,et al.  Raman spectroscopic study of microcrystalline silica , 2007 .

[4]  D. McKeown.  Raman spectroscopy and vibrational analyses of albite: From 25 °C through the melting temperature , 2005 .

[5]  M. Morris,et al.  Infrared and Raman Spectroscopy , 2000 .

[6]  M. Brunelli,et al.  Incommensurate modulation at 165 °C of intermediate tridymite , 2005 .

[7]  D. Nash,et al.  A reconnaissance laser Raman and Fourier transform infrared survey of silcretes from the Kalahari Desert, Botswana , 2004 .

[8]  R. Roessler,et al.  Raman and cathodoluminescence spectroscopic investigations on Permian fossil wood from Chemnitz--a contribution to the study of the permineralisation process. , 2004, Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.

[9]  S. Ríos,et al.  Moganite and water content as a function of age in agate an XRD and thermogravimetric study , 2004 .

[10]  K. A. Rodgers,et al.  Cinnabar, livingstonite, stibnite and pyrite in Pliocene silica sinter from Northland, New Zealand , 2004, Mineralogical Magazine.

[11]  V. Struzhkin,et al.  Raman spectroscopy of metals, high‐temperature superconductors and related materials under high pressure , 2003 .

[12]  I. Swainson,et al.  Infrared and Raman spectroscopy studies of the α–β phase transition in cristobalite , 2003 .

[13]  K. Rodgers,et al.  Laser Raman identification of silica phases comprising microtextural components of sinters , 2003, Mineralogical Magazine.

[14]  P. Heaney,et al.  Evidence for an I2/a to Imab phase transition in the silica polymorph moganite at ~570 K , 2001 .

[15]  P. English.  Formation of analcime and moganite at Lake Lewis, central Australia: significance of groundwater evolution in diagenesis , 2001 .

[16]  M. Bustillo.  Cherts with Moganite in Continental Mg-Clay Deposits: An Example of , 2001 .

[17]  G. Cressey,et al.  The occurrence, detection and significance of moganite (SiO2) among some silica sinters , 2001, Mineralogical Magazine.

[18]  J. Leger,et al.  The high-pressure behaviour of the “moganite” polymorph of SiO2 , 2001 .

[19]  E. Salje,et al.  Nanoquartz vs. macroquartz: a study of the α↔β phase transition , 2001 .

[20]  G. Parthasarathy,et al.  Occurrence of moganite-rich chalcedony in Deccan flood basalts, Killari, Maharashtra, India , 2001 .

[21]  D. Keen,et al.  LETTER TO THE EDITOR: Simultaneous analysis of changes in long-range and short-range structural order at the displacive phase transition in quartz , 2000 .

[22]  K. Campbell,et al.  Mineralogical and textural changes accompanying ageing of silica sinter , 2000 .

[23]  U. Bismayer.  Hard Mode Spectroscopy of Phase Transitions , 2000 .

[24]  S. Roberts,et al.  The nature of crystalline silica from the TAG submarine hydrothermal mound, 26°N Mid Atlantic Ridge , 1999 .

[25]  J. Götze,et al.  Occurrence and distribution of “moganite” in agate/chalcedony: a combined micro-Raman, Rietveld, and cathodoluminescence study , 1998 .

[26]  Michael A. Carpenter,et al.  Elastic anomalies in minerals due to structural phase transitions , 1998 .

[27]  K. Knight,et al.  Calibration of excess thermodynamic properties and elastic constant variations associated with the alpha beta phase transition in quartz , 1998 .

[28]  K. Knight,et al.  Calibration of excess thermodynamic properties and elastic constant variations associated with the α ↔ β phase transition in quartz , 1998 .

[29]  S. Gíslason,et al.  Kinetic and thermodynamic properties of moganite, a novel silica polymorph , 1997 .

[30]  P. Heaney.  Moganite as an indicator for vanished evaporites; a testament reborn? , 1995 .

[31]  Charles C. Kim,et al.  Vibrational analysis of dioptase Cu6Si6O18 · 6(H2O) and its puckered six-membered ring , 1995 .

[32]  R. Hemley,et al.  Raman spectroscopic study of microcrystalline silica , 1994 .

[33]  M. Vallade,et al.  Lattice dynamical behavior of anhydrous silica , 1994 .

[34]  P. Heaney,et al.  Structure and chemistry of the low-pressure silica polymorphs , 1994 .

[35]  P. Heaney.  A proposed mechanism for the growth of chalcedony , 1993 .

[36]  W. Schmahl.  Athermal transformation behaviour and thermal hysteresis at the SiO2-α/β-cristobalite phase transition , 1993 .

[37]  G. Miehe,et al.  Crystal structure of moganite; a new structure type for silica , 1992 .

[38]  E. Salje.  Hard mode Spectroscopy: Experimental studies of structural phase transitions , 1992 .

[39]  P. Heaney,et al.  The Widespread Distribution of a Novel Silica Polymorph in Microcrystalline Quartz Varieties , 1992, Science.

[40]  I. P. Swainson,et al.  Landau free energy and order parameter behaviour of the α/β phase transition in cristobalite , 1992 .

[41]  Martin T. Dove,et al.  Landau free energy and order parameter behaviour of theα/βphase transition in cristobalite , 1992 .

[42]  P. Heaney,et al.  Observations of the alpha -beta phase transition in quartz; a review of imaging and diffraction studies and some new results , 1991 .

[43]  E. Dowty.  Fully automated microcomputer calculation of vibrational spectra , 1987 .

[44]  B. Berge,et al.  Raman scattering investigation of the α-β transition and of the incommensurate phase in quartz , 1984 .

[45]  O. W. Floke.  Moganite, a new microcrystalline silica mineral , 1984 .

[46]  S. Amelinckx,et al.  The α → β transition in amethyst quartz as studied by electron microscopy and diffraction. The interaction of dauphiné with Brazil twins , 1977 .

[47]  R. Fournier.  Chemical geothermometers and mixing models for geothermal systems , 1977 .

[48]  A. Wright,et al.  The α—β transition in the cristobalite phases of SiO2 and AIPO4 I. X-ray studies , 1976 .

[49]  J. B. Jones,et al.  A new microcrystalline silica from Gran Canaria , 1976 .

[50]  W. G. Fateley.  Infrared and Raman selection rules for molecular and lattice vibrations : the correlation method , 1972 .

[51]  J. Scott.  Evidence of Coupling Between One- and Two-Phonon Excitations in Quartz , 1968 .

[52]  D. O'shea,et al.  Raman Scattering Study of the Alpha-Beta Phase Transition in Quartz , 1967 .

[53]  R. Fournier,et al.  Estimation of underground temperatures from the silica content of water from hot springs and wet-steam wells , 1966 .

[54]  C. Raman,et al.  The α-β; Transformation of Quartz , 1940, Nature.

[55]  G. Landsberg,et al.  Lichtzerstreuung in Kristallen bei hoher Temperatur , 1929 .