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- Gibbs, G.V., Hill, F.C., Boisen, M.B., Jr., and Downs, R.T. (1998) Power law relationships between bond length, bond strength and electron density distributions. Physics and Chemistry of Minerals 25, 585-590. ( pdf file )
- Gibbs, G.V., Boisen, M.B., Jr., Hill, F.C., Tamada, O., and Downs, R.T. (1998) SiO and GeO bonded interactions as inferred from the bond critical point properties of electron density distributions. Physics and Chemistry of Minerals, 25,574-584. ( pdf file )
- Jacobsen, S.D., Smyth, J.R., Swope, R.J., and Downs, R.T. (1998) Rigid-body character of the SO 4 groups in celestite, anglesite, and barite. Canadian Mineralogist, 36, 1045-1055. ( pdf abstract )
- Cohen, R. E., Fei, Y., Downs, R.T., Mazin, I.I., and Isaak, D.G. (1998) Magnetic collapse and the behavior of transition metal oxides: FeO at high pressures, in High-Pressure Materials Research , R. M. Wentzcovitch et al., eds., pp. 27-37, Symposium Proceedings Vol. 499, Materials Research Society, Warrendale, Pennsylvania.
- Prewitt, C.T. and Downs, R.T. (1998) High-Pressure Crystal Chemistry. Reviews in Mineralogy, 37, Ultrahigh-Pressure Mineralogy: Physics and Chemistry of the Earth?s Deep Interior , Russell J. Hemley, Editor. Mineralogical Society of America, Washington DC.
- Gibbs, G.V., Hill, F.C., Boisen, M.B., Jr., and Downs, R.T. (1999) Molecules as a basis for modeling the force field of silica. In Structure and Imperfections in Amorphous and Crystalline SiO 2 . Rod Devine, editor, John Wiley and Sons, Chapter 6, 151-163.
- Downs, R.T., Yang, H., Hazen, R.M., Finger, L.W., and Prewitt, C.T. (1999) Compressibility mechanisms of alkali feldspars: New data from reedmergnerite. American Mineralogist , 84, 333-340. ( pdf file )
- Sprague, A.L., Roush, T.L., Downs, R.T., Righter, K. (2000) Response to comment on "Comparison of laboratory emission spectra with Mercury telescopic data" by Melissa Lane. Icarus 143, 409-411. ( pdf file )
- Holl, C.M., Smyth, J.R., Lausten, H.M.S., Jacobsen, S.D., and Downs, R.T. (2000) Compression of witherite to 8 GPa and the crystal structure of BaCO 3 II. Physics and Chemistry of Minerals , 27, 467-473. ( pdf file )
- Hazen, R.M., and Downs, R.T. (2000) High-Temperature and High-Pressure Crystal Chemistry , Reviews in Mineralogy and Geochemistry, Volume 41. Robert M. Hazen and Robert T. Downs, Editors. Mineralogical Society of America, Washington DC.
- Angel, R.J., Downs, R.T., and Finger, L.W. (2000) High-temperature ? high-pressure diffractometry. Reviews in Mineralogy and Geochemistry, 41, High-Temperature and High-Pressure Crystal Chemistry , Robert M. Hazen and Robert T. Downs, Editors. Mineralogical Society of America, Washington DC.
- Downs, R.T. (2000) Analysis of harmonic displacement factors. Reviews in Mineralogy and Geochemistry, 41, High-Temperature and High-Pressure Crystal Chemistry , Robert M. Hazen and Robert T. Downs, Editors. Mineralogical Society of America, Washington DC.
- Downs, R.T., and Heese, P.J. (2000) Animation of crystal structure variations with pressure, temperature and composition. Reviews in Mineralogy and Geochemistry, 41, High-Temperature and High-Pressure Crystal Chemistry , Robert M. Hazen and Robert T. Downs, Editors. Mineralogical Society of America, Washington DC.
- Hazen, R.M., Downs, R.T., and Prewitt, C.T. (2000) Principles of comparative crystal chemistry. Reviews in Mineralogy and Geochemistry, 41, High-Temperature and High-Pressure Crystal Chemistry , Robert M. Hazen and Robert T. Downs, Editors. Mineralogical Society of America, Washington DC.
- Thompson, R.M., and Downs, R.T. (2001) Quantifying distortion from ideal closest-packing in a crystal structure with analysis and application. Acta Crystallographica B57, 119-127. ( pdf file )
- Righter, K., and Downs, R.T. (2001) The crystal structures of synthetic Re- and PGE-bearing magnesioferrite spinels: Implications for impacts, accretion and the mantle. Geophysical Research Letters , 28, 619-622.
- Thompson, R.M., and Downs, R.T. (2001) The systematic generation of all nonequivalent closest-packed stacking sequences of length N using group theory. Acta Crystallographica, B57, 766-771. ( pdf file )
- Lager, G.A., Downs, R.T. Origlieri, M., and Garoutte, R. (2002) High-pressure single-crystal X-ray diffraction study of hydrogarnet: Evidence for a phase transition from Ia3d to I43d symmetry at 5 GPa. American Mineralogist 87, 642-647. ( pdf file )
- Downs, R.T., Gibbs, G.V., Boisen, M.B.Jr., and Rosso, K.M. (2002) A comparison of procrystal and ab initio representations of the electron-density distributions of minerals. Physics and Chemistry of Minerals 29, 369-385. ( pdf file )
- Downs, R.T. and Hall-Wallace, M. (2003) The American Mineralogist Crystal Structure Database. American Mineralogist 88, 247-250. ( pdf file )
- Downs, R.T. (2003) Topology of the pyroxenes as a function of temperature, pressure, and composition as determined from the procrystal electron density. American Mineralogist 88, 556-566. ( pdf file )
- Thompson, R.M. and Downs, R.T. (2003) Model pyroxenes I: Ideal pyroxene topologies. American Mineralogist 88, 653-666. ( pdf file )
- Denton, M.B., Sperline, R.P., Giles, J.H., Gilmore, D.A., Pommier, C.J.S., and Downs, R.T. (2003) Advances in the application of array detectors for improved chemical analysis, Part I. Comparison of qualitative analyses using large, computer-based Raman spectral libraries. Australian Journal of Chemistry 56, 117-131. ( pdf file )
- Downs, R.T. (2003) The Berry Medal for 2002 to Robert T. Downs. The Canadian Mineralogist 41, 243-245. ( pdf file )
- Gibbs, G.V., Cox, D.F., Boisen, M.B., Jr., Downs, R.T., and Ross, N.L. (2003) The electron localization function: a tool for locating favorable proton docking sites in the silica polymorphs. Physics and Chemistry of Minerals, 30, 305-316. ( pdf file )
- Origlieri, M.J., Downs, R.T., Thompson, R.M., Pommier, C.J.S., Denton, M.B., and Harlow, G.E. (2003) High-pressure crystal structure of kosmochlor, NaCrSi 2 O 6 , and systematics of anisotropic compression in pyroxenes. American Mineralogist, 88, 1025-1032. ( pdf file ) ( erratum )
- Wang, Z., Downs, R.T., Pischedda, V., Shetty, R., Saxena, S.K., Zha, C.S., Zhao, Y.S., Schiferl, D., and Waskowska, A. (2003) High-pressure X-ray diffraction and Raman spectroscopic studies of the tetragonal spinel CoFe 2 O 4 . Physical Review B 68, 094101. ( pdf file )
- Wang, Z., Zhao, Y., Schiferl, D., Zha, C.S., Downs, R.T., Sekine, T. (2003) Critical pressure for weakening of size-induced stiffness in spinel-structure Si 3 N 4 nanocrystals. Applied Physics Letters , 83, 3174-3176. ( pdf file )
- Pommier, C.J.S., Denton, M.B., and Downs, R.T. (2003) Raman spectroscopic study of spodumene (LiAlSi 2 O 6 ) through the pressure-induced phase change from C 2/ c to P 2 1 / c . Journal of Raman Spectroscopy , 34, 769-775. ( pdf file )
- Gibbs, G.V., Whitten, A.E., Spackman, M.A., Stimpfl, M., Downs, R.T., and Carducci, M.D. (2003) An exploration of theoretical and experimental electron density distributions and SiO bonded interactions for the silica polymorph coesite. Journal of Physical Chemistry B , ASAP Web Release Date: 01-Nov-2003; DOI: 10.1021/jp030583+ ( pdf file )
- Wang, Z., Zhao, Y., Schiferl, D., Qian, J., Downs, R.T., Mao, H-K., and Sekine, T. (2003) Threshold pressure for disappearance of size-induced effect in spinel-structure Ge3N4 nanocrystals. Journal of Physical Chemistry B Letters , ASAP Web Release Date: 02-Dec-2003; DOI: 10.1021/jp036436t ( pdf file )
- Ross, N.L. and Downs, R.T. (2003) "Stuffed" framework structures at high pressure. In NATO ASI Series: High-Pressure Crystallography , P.F. McMillan and A. Katrusiak, Eds., Kluwer Academic Press.
- Thompson, R.M., and Downs, R.T. (2004) Model pyroxenes II: Structural variation as a function of tetrahedral rotation. American Mineralogist 89, 614-628. ( pdf file )
- Bobev, S., and Tait, K.T. (2004) Methanol - inhibitor or promotor of the formation of gas hydrates from deuterated ice? American Mineralogist 89, 1208-1214. ( pdf file )
- Clark, C.M., and Downs, R.T. (2004) Using the American Mineralogist Crystal Structure Database in the classroom. Invited paper, Journal of Geoscience Education 51, 76-80. ( pdf file )
- Downs, R.T., and Hazen, R.M. (2004) Chiral indices of crystalline surfaces as a measure of enantioselective potential. Invited paper, Journal of Molecular Catalysis A: Chemical 216, 273-285. ( pdf file )
- Wang, Z, Zhao, Y., Schiferl, D., Zha, C.S., and Downs, R.T. (2004) Pressure induced increase of particle size and resulting weakening of elastic stiffness of CeO 2 nanocrystals. Applied Physics Letters 85, 124-126. ( pdf file )
- Wang, Z, Tait, K., Zhao, Y., Schiferl, D., Zha, C.S., Uchida, H., and Downs, R.T. (2004) Size-induced reduction of transition pressure and enhancement of bulk modulus of AlN nanocrystals. Journal of Physical Chemistry B 108, 11506-11508. ( pdf file )
- Wang, Z, Zhao, Y., Tait, K., Liao, X., Schiferl, D., Zha, C.S., Downs, R.T., Qian J., Zhu, Y., and Shen, T. (2004) A quenchable superhard carbon phase synthesized by cold compression of carbon nanotubes. Proceedings of the National Academy of Sciences of the United States of America 101, 13699-13702 ( pdf file )
- Le Bail, A., Chateigner, D., Chen, X., Ciriotti, M., Cranswick, L.M.D., Downs, R.T., Lutterotti, L., Rajan, H., Yokochi, A.F.T.
(2004)
Does open data better serve the crystallographic community?
International Union of Crystallography Newsletter 12, 27.
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- Downs, R.T., Yang, H., Hazen, R.M., and Finger, L.W. (1997) The high-pressure crystal chemistry of the alkali feldspars: New data from reedmergnerite, NaBSi 3 O 8 . EOS Transactions, AGU, Spring Meeting Supplement, 78 (17) S314
- Cohen, R.E., Fei, Y., Mazin, I.I., Downs, R.T., and Isaak, D.G. (1997) Phase transitions in transition metal oxides and unusual polytypism in high pressure FeO. EOS Transactions, AGU, Fall Meeting Supplement, 78 (46) F743
- Downs, R.T., Teter, D.M., and Gibbs, G.V. (1997) A Pro-crystal electron density analysis of potassium-oxygen bonding in microcline and KTP as a function of pressure. EOS Transactions, AGU, Fall Meeting Supplement, 78 (46) F754
- Downs, R.T. (1998) Computer graphics simulation of compression mechanisms in crystals. IUCR-HP98, Argonne, Abstracts, 21
- Thompson, R.M., and Downs, R.T. (1999) Quantitative analysis of the closest-packing of anions in mineral structures as a function of pressure, temperature, and compositions. EOS Transactions, AGU, Fall Meeting Supplement, 80 (46) F1107.
- Downs, R.T., Gibbs, G.V., and Boisen M.B., Jr. (1999) Topological analysis of the P21/c to C2/c transition in pyroxenes as a function of temperature and pressure. EOS Transactions, AGU, Fall Meeting Supplement, 80 (46) F1140.
- Righter, K., and Downs, R.T. (2000) Magnesioferrite spinel as the host phase for iridium and other highly siderophile elements at the cretaceous-tertiary boundary. Meteoritical Society Meeting. Meteoritics & Planetary Science 35: A136-A137, Supplement S Sep 2000
- Downs, R.T., Gibbs, G.V., Giovanni, M.K., Boisen, M.B.Jr., and Rosso, K.M. (2001) A comparison of procrystal and first-principles crystal electron density distributions with application to understanding the phase changes in pyroxenes. In Eleventh Annual V.M. Goldschmidt Conference, Abstract#3902, LPI Contribution No. 1088, Lunar and Planetary Institute, Houston (CD-ROM). May 20-24, Hot Springs, VA.
- Thompson, R.M., Downs, R.T., and Lienert, C. (2001) Ideal Pyroxene Topologies. In Eleventh Annual V.M. Goldschmidt Conference, Abstract#3149, LPI Contribution No. 1088, Lunar and Planetary Institute, Houston (CD-ROM). May 20-24, Hot Springs, VA.
- Thompson, R.M., Downs, R.T., and Teter, D.M. (2001) Packing systematics of stishovite. EOS Transactions, AGU, Fall Meeting Supplement, 82 (47) F1156. ( pdf abstract )
- Origlieri, M.J., Downs, R.T., and Harlow, G.E. (2001) Compression mechanism of the pyroxene kosmochlor. EOS Transactions, AGU, Fall Meeting Supplement, 82 (47) F1393. ( pdf abstract )
- Pommier, C.J.S., Denton, M.B., and Downs, R.T. (2002) Polarized Raman spectroscopic study of the pressure-induced phase change from C2/c to P21/c in spodumene. Pittcon 1747P, New Orleans, LA, March 17-22, 2002. ( pdf file )
- Lager, G.A., Marshall, W.G., and Downs, R.T. (2002) Keynote address: Re-examination of the hydrogarnet structure at high pressure using neutron powder methods: Comparison with single-crystal X-ray and theoretical results. 18th General Meeting of the International Mineralogical Association , 1-6 Sept, 2002, Edinburgh, Scotland. Programme With Abstracts, page 82.
- Origlieri, M.J., Thompson, R.M., Downs, R.T., and Gibbs, G.V. (2002) The relationship between compression anisotropy observed in the pyroxenes and oxide anion non-bonded repulsions. 18th General Meeting of the International Mineralogical Association , 1-6 Sept, 2002, Edinburgh, Scotland. Programme With Abstracts, page 71.
- Downs, R.T., and Hall-Wallace, M. (2002) A Database of Crystal Structures Published in the American Mineralogist and The Canadian Mineralogist and It?s Use as a Resource in the Classroom. 18th General Meeting of the International Mineralogical Association , 1-6 Sept, 2002, Edinburgh, Scotland. Programme With Abstracts, page 128.
- Thompson, R.M., and Downs, R.T. (2002) Model Pyroxenes and Transition Pathways. 18th General Meeting of the International Mineralogical Association , 1-6 Sept, 2002, Edinburgh, Scotland. Programme With Abstracts, page 85.
- Pommier, C.J.S., Denton, M.B., and Downs, R.T. (2003) Raman spectroscopic study of spodumene through the pressure-induced phase change from C2/c to P21/c. Pittcon 1730-3, Orlando, FL, March 9-14, 2003.
- Ross, N.L., and Downs, R.T. (2003) High-pressure crystal chemistry: ?Stuffed? framework structures at high-pressure. International School of Crystallography , High Pressure Crystallography, 4-15 June. Erice, Italy
- Hazen, R.M. and Downs, R.T. (2003) Chiral mineral surfaces and their chiral index. The Geological Society of America Annual Meeting, Seattle Washington. November 2-5, 2003. ( pdf abstract )
- Gibbs, G.V., Whitten, A., Spackman, M., Simpfl, M., Carducci, M., and Downs, R.T. (2003) The silica polymorph coesite: An exploration of the electron density. The Geological Society of America Annual Meeting, Seattle Washington. November 2-5, 2003. ( pdf abstract )
- McIntosh, B., Denton, M.B., Downs, R.T., Becker, D. (2003) Smart Raman instrument for Mars Science Laboratory. Mars Exploration Program Assessment Group, Sept 10-11, Jet Propulsion Laboratory, Pasadena, CA. ( pdf file )
- Uchida, H., and Downs, R.T. (2003) Single-crystal X-ray diffraction studies on spinels from the San Carlos Volcanic Field, Arizona. In Geochimica et Cosmochimica Acta 67, A497 Supplement, Goldschmidt Conference, Sept 7-12, Kurashiki Japan. ( pdf file )
- Tait K.T., Zhao, Y., and Downs, R.T. (2004) Investigations into the stability, morphology, and crystal structure of the coexistence of s-I and s-II methane-ethane and methane-propane clathrate hydrates: occurrence and geological implications. Lab Directed Research Dollars Review at LANSCE, Los Alamos, New Mexico. March 17, 2004.
- McIntosh, B. Denton, M.B., and Downs, R.T. (2004) Process Raman on Earth and research Raman on Mars - How are they related? Pittcon March 11, 2004. (Session: 24300-1000). Chicago, IL.
- Liermann H. P., Downs R. T., Yang H. (2004) Raman spectroscopy of order/disorder in pseudobrookite (MgTi2O5): Implication for the determination of the thermal history of planetary materials by remote sensing. 32nd IGC - Florence 2004.
- Hazen, R.M., Asthagiri, A., Teng, H., and Downs, R.T. (2004) Geochemical pathways to the origin of biochemical homochirality. Division of Geochemistry, American Chemical Society National Meeting, Philadelphia, PA, Aug 22-26. ( html file )
- Downs, R.T., Liermann, H.P., and Yang, H. (2004) The analysis of Mg and Ti order/disorder in pseudobrookite by Raman spectroscopy: Implications for the geological exploration of Mars. Geological Association of Canada - Mineralogical Association of Canada Annual Meeting, St. Catherines 2004. SS01-06.
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- Capitalization, University of Arizona, (1996) $240,000.
- A device to apply hydrostatic high-pressure to crystals (1999-2001) Faculty Small Grants Program, University of Arizona Foundation, $5000.
- Compression mechanisms of upper mantle minerals (1999-2002) National Science Foundation, $186,997.
- Advancing Computational and Visualization Skills in Geosciences (2000-2002) National Science Foundation, $52,148. Joint, with M. Hall-Wallace (P.I.), R. F. Butler, P. Kresan, J. Pelletier.
- Compression mechanisms of upper mantle minerals, Research Experience for Undergraduates (2000-2002) National Science Foundation, $12,500.
- The crystal structure database and analysis tools project (2001-2004) National Science Foundation, $350,000.
- University of Nevada at Las Vegas subcontract (2002) Development of Windows-based single crystal diffractometer software, Department of Energy, $34,815.
- University of Nevada at Las Vegas subcontract (2002-2003) Development of Windows-based single crystal diffractometer software for Argonne National Labs' Advance Photon Source, Department of Energy, $83,669.
- A high performance Raman spectroscopy system for Mars surface studies. (2003-2005) Co-PI: B. McIntosh (Hamilton Sundstrand Sensor Systems), M.B. Denton (U of Arizona), R.T. Downs (UofA) and W. Doyle (Axiom Analytical, Inc.) NASA, $1,491,770.
- Clathrate Hydrates Science and Technology. (2003-2005) PI: Yusheng Zhao (Los Alamos) Co-PI: D.L. Bish, L.L. Daemen, A. Migliori, R.P. Currier, L.R. Pratt, P.C. Lichtner, D.D. Hickmott. Collaborators: H-K Mao, R. Hemley, J. Parise, R.T. Downs. Department of Energy $4,350,000.
- Combination of private funding and matching funds from the College of Science for a new Bruker X8Apex single-crystal diffractometer and a Bruker D8Advance powder diffractometer plus laboratory renovations, $450,000.
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- Jan 24, 2001 Arizona Star Press Release
- Jan 29, 2001 Arizona Star UA's Raman spectrometer is the last word on mineral ID
- Oct 2, 2002 Arizona Star UA scientists developing Star Trek-like device
- Oct 3, 2002 Arizona Star UA tool peeks inside rocks
- Oct 4, 2002 Spectroscopy Now U Arizona Tool To Peek Inside Martian Rocks - Star Trek Style!
- Aug 20, 2004 Science, NetWatch - Crystal Palace .
- Sept 16, 2004 Nature, Research Highlights: Nanotubes get hard under pressure .
- Sept, 2004 Nanotechnology: Nanotubes harden up under pressure
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