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Ray L. Frost - One of the best experts on this subject based on the ideXlab platform.
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structure of selected basic zinc copper ii Phosphate Minerals based upon near infrared spectroscopy implications for hydrogen bonding
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2011Co-Authors: Ray L. Frost, Jagannadha B Reddy, Sara J Palmer, Eloise C KeeffeAbstract:The NIR spectra of reichenbachite, scholzite and parascholzite have been studied at 298 K. The spectra of the Minerals are different, in line with composition and crystal structural variations. Cation substitution effects are significant in their electronic spectra and three distinctly different electronic transition bands are observed in the near-infrared spectra at high wavenumbers in the 12,000-7600 cm(-1) spectral region. Reichenbachite electronic spectrum is characterised by Cu(II) transition bands at 9755 and 7520 cm(-1). A broad spectral feature observed for ferrous ion in the 12,000-9000 cm(-1) region both in scholzite and parascholzite. Some what similarities in the vibrational spectra of the three Phosphate Minerals are observed particularly in the OH stretching region. The observation of strong band at 5090 cm(-1) indicates strong hydrogen bonding in the structure of the dimorphs, scholzite and parascholzite. The three Phosphates exhibit overlapping bands in the 4800-4000 cm(-1) region resulting from the combinations of vibrational modes of (PO(4))(3-) units.
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raman spectroscopic study of the uranyl Phosphate Minerals phosphuranylite and yingjiangite
Journal of Raman Spectroscopy, 2008Co-Authors: Ray L. Frost, Jiři Cejka, Godwin A AyokoAbstract:Raman spectra of phosphuranylite and yingjiangite were measured, interpreted and compared with published infrared spectra of both Minerals. U-O bond lengths were calculated using the Bartlett-Cooney‘s empirical relations and the O-H-O hydrogen bond lengths were inferred on the basis of Libowitzky's empirical relation. The presence of oxonium and (H3O)+ ions, expected from the single crystal structure analysis of phosphuranylite, was not inferred from the Raman spectra. It was assumed that phosphuranylite and yingjiangite are identical and the name yingjiangite should be discarded because the name phosphuranylite has priority.
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An infrared spectroscopic study of the basic copper Phosphate Minerals: Cornetite, libethenite, and pseudomalachite
American Mineralogist, 2003Co-Authors: Wayde N. Martens, Ray L. FrostAbstract:The molecular structures of the basic copper Phosphate Minerals pseudomalachite, libethenite, and cornetite were studied using a combination of infrared emission spectroscopy, infrared absorption, and Raman spectroscopy. Infrared emission spectra of these Minerals were obtained over the temperature range 100 to 1000 °C. The infrared spectra of the three Minerals are different, in line with differences in crystal structure and composition. The absorption spectra are similar, particularly in the OH stretching region, but characteristic differences in the bending regions are observed. Differences are also observed in the Phosphate stretching and bending regions. The IR emission of the basic copper Phosphates studied shows that the Minerals are completely dehydroxylated by 550 °C.
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The Basic Copper Phosphate Minerals Pseudomalachite, Ludjibaite and Reichenbachite: An Infrared Emission and Raman Spectroscopic Study
Neues Jahrbuch Fur Mineralogie-abhandlungen, 2003Co-Authors: Wayde N. Martens, Ray L. Frost, Peter A. WilliamsAbstract:The molecular structures of the trimorphous basic copper Phosphate Minerals pseudomalachite, ludjibaite and reichenbachite have been studied using a combination of infrared emission spectroscopy and Raman spectroscopy. Infrared emission spectra have been obtained over the temperature range 100 to 1000 degrees Celsius. Infrared emission spectra of the three Minerals are different, in line with differences in crystal structure and composition. IR emission spectra show that the Minerals are completely dehydroxylated by 550 degrees Celsius. The thermal decomposition patterns for the three Minerals are different and reflect their stability. Raman spectra are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate stretching and bending regions.
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Vibrational spectroscopy of the basic manganese and ferric Phosphate Minerals : strunzite, ferrostrunzite and ferristrunzite
Neues Jahrbuch für Mineralogie - Monatshefte, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Jacob Kloprogge, Peter A. WilliamsAbstract:The Raman spectra of strunzite, ferristrunzite and ferrostrunzite have been obtained at 298 and 77K using a combination of a thermal stage and Raman microscopy. These spectra are compared with their infrared spectra. The vibrational spectra of the two Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the hydroxyl-stretching region exists, particularly at 298K, but characteristic differences in the OH deformation regions are observed. Significant shifts in the position of the Raman bands are observed by obtaining the spectra at 77K. Differences are also observed in the Phosphate stretching and deformation regions.
Peter Leverett - One of the best experts on this subject based on the ideXlab platform.
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vibrational spectroscopy of the basic copper Phosphate Minerals pseudomalachite ludjibaite and reichenbachite
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Therese E Johnson, Peter LeverettAbstract:The vibrational spectra of pseudomalachite, reichenbachite and ludjibaite have been obtained at 298 K using a combination of FTIR and Raman microscopy. The vibrational spectra of the Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite exists, particularly in the OH stretching region, but characteristic differences in the OH deformation regions are observed. Differences are also observed in the Phosphate stretching and deformation regions.
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raman spectroscopy of the basic copper Phosphate Minerals cornetite libethenite pseudomalachite reichenbachite and ludjibaite
Journal of Raman Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Peter LeverettAbstract:Raman spectra of cornetite, libethenite, pseudomalachite, reichenbachite and ludjibaite were obtained at 298 and 77 K using a Raman microprobe in combination with a thermal stage. Raman spectra of cornetite, libethenite and pseudomalachite are different, in line with differences in crystal structure and composition. Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate deformation and stretching regions.
Wayde N. Martens - One of the best experts on this subject based on the ideXlab platform.
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The Basic Copper Phosphate Minerals Pseudomalachite, Ludjibaite and Reichenbachite: An Infrared Emission and Raman Spectroscopic Study
Neues Jahrbuch Fur Mineralogie-abhandlungen, 2003Co-Authors: Wayde N. Martens, Ray L. Frost, Peter A. WilliamsAbstract:The molecular structures of the trimorphous basic copper Phosphate Minerals pseudomalachite, ludjibaite and reichenbachite have been studied using a combination of infrared emission spectroscopy and Raman spectroscopy. Infrared emission spectra have been obtained over the temperature range 100 to 1000 degrees Celsius. Infrared emission spectra of the three Minerals are different, in line with differences in crystal structure and composition. IR emission spectra show that the Minerals are completely dehydroxylated by 550 degrees Celsius. The thermal decomposition patterns for the three Minerals are different and reflect their stability. Raman spectra are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate stretching and bending regions.
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An infrared spectroscopic study of the basic copper Phosphate Minerals: Cornetite, libethenite, and pseudomalachite
American Mineralogist, 2003Co-Authors: Wayde N. Martens, Ray L. FrostAbstract:The molecular structures of the basic copper Phosphate Minerals pseudomalachite, libethenite, and cornetite were studied using a combination of infrared emission spectroscopy, infrared absorption, and Raman spectroscopy. Infrared emission spectra of these Minerals were obtained over the temperature range 100 to 1000 °C. The infrared spectra of the three Minerals are different, in line with differences in crystal structure and composition. The absorption spectra are similar, particularly in the OH stretching region, but characteristic differences in the bending regions are observed. Differences are also observed in the Phosphate stretching and bending regions. The IR emission of the basic copper Phosphates studied shows that the Minerals are completely dehydroxylated by 550 °C.
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Vibrational spectroscopy of the basic manganese and ferric Phosphate Minerals : strunzite, ferrostrunzite and ferristrunzite
Neues Jahrbuch für Mineralogie - Monatshefte, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Jacob Kloprogge, Peter A. WilliamsAbstract:The Raman spectra of strunzite, ferristrunzite and ferrostrunzite have been obtained at 298 and 77K using a combination of a thermal stage and Raman microscopy. These spectra are compared with their infrared spectra. The vibrational spectra of the two Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the hydroxyl-stretching region exists, particularly at 298K, but characteristic differences in the OH deformation regions are observed. Significant shifts in the position of the Raman bands are observed by obtaining the spectra at 77K. Differences are also observed in the Phosphate stretching and deformation regions.
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vibrational spectroscopy of the basic copper Phosphate Minerals pseudomalachite ludjibaite and reichenbachite
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Therese E Johnson, Peter LeverettAbstract:The vibrational spectra of pseudomalachite, reichenbachite and ludjibaite have been obtained at 298 K using a combination of FTIR and Raman microscopy. The vibrational spectra of the Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite exists, particularly in the OH stretching region, but characteristic differences in the OH deformation regions are observed. Differences are also observed in the Phosphate stretching and deformation regions.
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raman spectroscopy of the basic copper Phosphate Minerals cornetite libethenite pseudomalachite reichenbachite and ludjibaite
Journal of Raman Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Peter LeverettAbstract:Raman spectra of cornetite, libethenite, pseudomalachite, reichenbachite and ludjibaite were obtained at 298 and 77 K using a Raman microprobe in combination with a thermal stage. Raman spectra of cornetite, libethenite and pseudomalachite are different, in line with differences in crystal structure and composition. Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate deformation and stretching regions.
Peter A. Williams - One of the best experts on this subject based on the ideXlab platform.
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The Basic Copper Phosphate Minerals Pseudomalachite, Ludjibaite and Reichenbachite: An Infrared Emission and Raman Spectroscopic Study
Neues Jahrbuch Fur Mineralogie-abhandlungen, 2003Co-Authors: Wayde N. Martens, Ray L. Frost, Peter A. WilliamsAbstract:The molecular structures of the trimorphous basic copper Phosphate Minerals pseudomalachite, ludjibaite and reichenbachite have been studied using a combination of infrared emission spectroscopy and Raman spectroscopy. Infrared emission spectra have been obtained over the temperature range 100 to 1000 degrees Celsius. Infrared emission spectra of the three Minerals are different, in line with differences in crystal structure and composition. IR emission spectra show that the Minerals are completely dehydroxylated by 550 degrees Celsius. The thermal decomposition patterns for the three Minerals are different and reflect their stability. Raman spectra are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate stretching and bending regions.
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Vibrational spectroscopy of the basic manganese and ferric Phosphate Minerals : strunzite, ferrostrunzite and ferristrunzite
Neues Jahrbuch für Mineralogie - Monatshefte, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Jacob Kloprogge, Peter A. WilliamsAbstract:The Raman spectra of strunzite, ferristrunzite and ferrostrunzite have been obtained at 298 and 77K using a combination of a thermal stage and Raman microscopy. These spectra are compared with their infrared spectra. The vibrational spectra of the two Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the hydroxyl-stretching region exists, particularly at 298K, but characteristic differences in the OH deformation regions are observed. Significant shifts in the position of the Raman bands are observed by obtaining the spectra at 77K. Differences are also observed in the Phosphate stretching and deformation regions.
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vibrational spectroscopy of the basic copper Phosphate Minerals pseudomalachite ludjibaite and reichenbachite
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Therese E Johnson, Peter LeverettAbstract:The vibrational spectra of pseudomalachite, reichenbachite and ludjibaite have been obtained at 298 K using a combination of FTIR and Raman microscopy. The vibrational spectra of the Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite exists, particularly in the OH stretching region, but characteristic differences in the OH deformation regions are observed. Differences are also observed in the Phosphate stretching and deformation regions.
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raman spectroscopy of the basic copper Phosphate Minerals cornetite libethenite pseudomalachite reichenbachite and ludjibaite
Journal of Raman Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Peter LeverettAbstract:Raman spectra of cornetite, libethenite, pseudomalachite, reichenbachite and ludjibaite were obtained at 298 and 77 K using a Raman microprobe in combination with a thermal stage. Raman spectra of cornetite, libethenite and pseudomalachite are different, in line with differences in crystal structure and composition. Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate deformation and stretching regions.
Theo Kloprogge - One of the best experts on this subject based on the ideXlab platform.
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vibrational spectroscopy of the basic copper Phosphate Minerals pseudomalachite ludjibaite and reichenbachite
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Therese E Johnson, Peter LeverettAbstract:The vibrational spectra of pseudomalachite, reichenbachite and ludjibaite have been obtained at 298 K using a combination of FTIR and Raman microscopy. The vibrational spectra of the Minerals are different, in line with differences in crystal structure and composition. Some similarity in the Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite exists, particularly in the OH stretching region, but characteristic differences in the OH deformation regions are observed. Differences are also observed in the Phosphate stretching and deformation regions.
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raman spectroscopy of the basic copper Phosphate Minerals cornetite libethenite pseudomalachite reichenbachite and ludjibaite
Journal of Raman Spectroscopy, 2002Co-Authors: Ray L. Frost, Wayde N. Martens, Peter A. Williams, Theo Kloprogge, Peter LeverettAbstract:Raman spectra of cornetite, libethenite, pseudomalachite, reichenbachite and ludjibaite were obtained at 298 and 77 K using a Raman microprobe in combination with a thermal stage. Raman spectra of cornetite, libethenite and pseudomalachite are different, in line with differences in crystal structure and composition. Raman spectra of the three polymorphs pseudomalachite, reichenbachite and ludjibaite are similar, particularly in the stretching region, but characteristic differences in the deformation regions are observed. Differences are also observed in the Phosphate deformation and stretching regions.