'Soft' phonon modes, structured diffuse scattering and the crystal chemistry of Fe-bearing sphalerites

Withers, Ray L; Welberry, T R; Pring, Allan; Tenailleau, Cristophe; Yun, Liu

doi:10.1016/j.jssc.2004.12.011

Title: 'Soft' phonon modes, structured diffuse scattering and the crystal chemistry of Fe-bearing sphalerites

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Abstract

Electron diffraction has been used to carefully investigate the reciprocal lattices of a range of iron-bearing sphalerites looking for evidence of Fe clustering and/or Fe/Zn ordering in the form of either additional satellite reflections or a structured diffuse intensity distribution accompanying the strong Bragg reflections of the underlying sphalerite-type average structure. While a highly structured diffuse intensity distribution in the form of transverse polarized {l_brace}110{r_brace}* sheets of diffuse intensity has been detected and found to be characteristic of all compositions, it does not appear to arise from Fe clustering and/or Fe/Zn ordering. Rather inherently low frequency, and therefore strongly thermally excited, phonon modes propagating along reciprocal space directions perpendicular to each of the six <110> real space directions of the average structure are suggested to be responsible for these {l_brace}110{r_brace}* sheets of diffuse intensity. Monte Carlo simulation (for a range of Zn-S, Zn-Zn and S-S interaction strengths) and subsequent Fourier transformation is used to confirm the existence of these low-frequency phonon modes of distortion as well as to show that they are an intrinsic, predictable property of the corner-connected tetrahedral structure of sphalerite. The low-frequency phonon modes involve coupled (Zn, Fe) and S motion in one-dimensional strings along <110> realmore » space directions.« less

Authors:

Withers, Ray L ^[1]; Welberry, T R ^[1]; Pring, Allan ^[2]; Tenailleau, Cristophe ^[2]; Yun, Liu ^[1]

Research School of Chemistry, Australian National University, Canberra, ACT, 0200 (Australia)
Mineralogy Department, South Australian Museum, Adelaide, South Australia (Australia)

Publication Date:: Tue Mar 15 00:00:00 EST 2005

OSTI Identifier:: 20725820

Resource Type:: Journal Article

Journal Name:: Journal of Solid State Chemistry

Additional Journal Information:: Journal Volume: 178; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2004.12.011; PII: S0022-4596(04)00653-X; Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0022-4596

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BRAGG REFLECTION; COMPUTERIZED SIMULATION; DIFFUSE SCATTERING; DISTRIBUTION; ELECTRON DIFFRACTION; FOURIER TRANSFORMATION; INTERACTIONS; IRON; MONTE CARLO METHOD; PHONONS; SPACE; SULFIDE MINERALS

Citation Formats


                    Withers, Ray L, Welberry, T R, Pring, Allan, Tenailleau, Cristophe, and Yun, Liu. 'Soft' phonon modes, structured diffuse scattering and the crystal chemistry of Fe-bearing sphalerites.  United States: N. p., 2005. 
        Web.  doi:10.1016/j.jssc.2004.12.011.

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                    Withers, Ray L, Welberry, T R, Pring, Allan, Tenailleau, Cristophe, & Yun, Liu. 'Soft' phonon modes, structured diffuse scattering and the crystal chemistry of Fe-bearing sphalerites.  United States.  https://doi.org/10.1016/j.jssc.2004.12.011

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                    Withers, Ray L, Welberry, T R, Pring, Allan, Tenailleau, Cristophe, and Yun, Liu. 2005.  
        "'Soft' phonon modes, structured diffuse scattering and the crystal chemistry of Fe-bearing sphalerites".  United States.  https://doi.org/10.1016/j.jssc.2004.12.011.

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@article{osti_20725820,

  title        = {'Soft' phonon modes, structured diffuse scattering and the crystal chemistry of Fe-bearing sphalerites},

  author       = {Withers, Ray L and Welberry, T R and Pring, Allan and Tenailleau, Cristophe and Yun, Liu},

  abstractNote = {Electron diffraction has been used to carefully investigate the reciprocal lattices of a range of iron-bearing sphalerites looking for evidence of Fe clustering and/or Fe/Zn ordering in the form of either additional satellite reflections or a structured diffuse intensity distribution accompanying the strong Bragg reflections of the underlying sphalerite-type average structure. While a highly structured diffuse intensity distribution in the form of transverse polarized {l_brace}110{r_brace}* sheets of diffuse intensity has been detected and found to be characteristic of all compositions, it does not appear to arise from Fe clustering and/or Fe/Zn ordering. Rather inherently low frequency, and therefore strongly thermally excited, phonon modes propagating along reciprocal space directions perpendicular to each of the six <110> real space directions of the average structure are suggested to be responsible for these {l_brace}110{r_brace}* sheets of diffuse intensity. Monte Carlo simulation (for a range of Zn-S, Zn-Zn and S-S interaction strengths) and subsequent Fourier transformation is used to confirm the existence of these low-frequency phonon modes of distortion as well as to show that they are an intrinsic, predictable property of the corner-connected tetrahedral structure of sphalerite. The low-frequency phonon modes involve coupled (Zn, Fe) and S motion in one-dimensional strings along <110> real space directions.},

  doi          = {10.1016/j.jssc.2004.12.011},

  url          = {https://www.osti.gov/biblio/20725820},
  journal      = {Journal of Solid State Chemistry},

  issn         = {0022-4596},

  number       = 3,

  volume       = 178,

  place        = {United States},

  year         = {Tue Mar 15 00:00:00 EST 2005},

  month        = {Tue Mar 15 00:00:00 EST 2005}

}

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