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Ray L Frost - One of the best experts on this subject based on the ideXlab platform.
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a vibrational spectroscopic study of the Phosphate Mineral vantasselite al4 po4 3 oh 3 9h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Andres Lopez, Frederick L TheissAbstract:We have studied the Phosphate Mineral vantasselite Al4(PO4)3(OH)3·9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027cm−1 are assigned to the PO43−ν1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the Phosphate units in the vantasselite structure. Raman bands at 1051, 1076 and 1090cm−1 are attributed to the PO43−ν3 antisymmetric stretching vibration. A comparison is made with the spectroscopy of wardite. Strong infrared bands at 1044, 1078, 1092, 1112, 1133, 1180 and 1210cm−1 are attributed to the PO43−ν3 antisymmetric stretching mode. Some of these bands may be due to δAl2OH deformation modes. Vibrational spectroscopy offers a mechanism for the study of the molecular structure of vantasselite.
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a vibrational spectroscopic study of the anhydrous Phosphate Mineral sidorenkite na3mn po4 co3
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Fernanda Maria BelottiAbstract:Sidorenkite is a very rare low-temperature hydrothermal Mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a Phosphate–carbonate of sodium and manganese. Such a formula with two oxyanions lends itself to vibrational spectroscopy. The sharp Raman band at 959 cm−1 and 1012 cm−1 are assigned to the PO43− stretching modes, whilst the Raman bands at 1044 cm−1 and 1074 cm−1 are attributed to the CO32− stretching modes. It is noted that no Raman bands at around 800 cm−1 for sidorenkite were observed. The infrared spectrum of sidorenkite shows a quite intense band at 868 cm−1 with other resolved component bands at 850 and 862 cm−1. These bands are ascribed to the CO32− out-of-plane bend (ν2) bending mode. The series of Raman bands at 622, 635, 645 and 704 cm−1 are assigned to the ν4 Phosphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the carbonate anion from D3h or even C2v.
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a raman and infrared spectroscopic analysis of the Phosphate Mineral wardite naal3 po4 2 oh 4 2 h2o from brazil
Science & Engineering Faculty, 2014Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Cristiano LanaAbstract:Abstract A wardite Mineral sample from Lavra Da Ilha, Minas Gerais, Brazil has been examined by vibrational spectroscopy. The Mineral is unusual in that it belongs to a unique symmetry class, namely the tetragonal-trapezohedral group. The structure of wardite contains layers of corner-linked –OH bridged MO6 octahedra stacked along the tetragonal C-axis in a four-layer sequence and linked by PO4 groups. Consequentially not all Phosphate units are identical. Two intense Raman bands observed at 995 and 1051 cm−1 are assigned to the ν1 PO 4 3 - symmetric stretching mode. Intense Raman bands are observed at 605 and 618 cm−1 with shoulders at 578 and 589 cm−1 are assigned to the ν4 out of plane bending modes of the PO 4 3 - . The observation of multiple bands supports the concept of non-equivalent Phosphate units in the structure. Sharp infrared bands are observed at 3544 and 3611 cm−1 are attributed to the OH stretching vibrations of the hydroxyl units. Vibrational spectroscopy enables subtle details of the molecular structure of wardite to be determined.
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a vibrational spectroscopic study of the Phosphate Mineral whiteite camn mg2al2 po4 4 oh 2 8 h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014Co-Authors: Ray L Frost, Ricardo Scholz, Andres LopezAbstract:Vibrational spectroscopy enables subtle details of the molecular structure of whiteite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. The infrared and Raman spectroscopy were applied to compare the molecular structure of whiteite with that of other Phosphate Minerals. The Raman spectrum of whiteite shows an intense band at 972 cm(-1) assigned to the ν1PO4(3-) symmetric stretching vibrations. The low intensity Raman bands at 1076 and 1173 cm(-1) are assigned to the ν3PO4(3-) antisymmetric stretching modes. The Raman bands at 1266, 1334 and 1368 cm(-1) are assigned to AlOH deformation modes. The infrared band at 967 cm(-1) is ascribed to the PO4(3-)ν1 symmetric stretching vibrational mode. The infrared bands at 1024, 1072, 1089 and 1126 cm(-1) are attributed to the PO4(3-)ν3 antisymmetric stretching vibrations. Raman bands at 553, 571 and 586 cm(-1) are assigned to the ν4 out of plane bending modes of the PO4(3-) unit. Raman bands at 432, 457, 479 and 500 cm(-1) are attributed to the ν2 PO4 and H2PO4 bending modes. In the 2600 to 3800 cm(-1) spectral range, Raman bands for whiteite are found 3426, 3496 and 3552 cm(-1) are assigned to AlOH stretching vibrations. Broad infrared bands are also found at 3186 cm(-1). Raman bands at 2939 and 3220 cm(-1) are assigned to water stretching vibrations. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of whiteite to be ascertained and compared with that of other Phosphate Minerals.
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a study of the Phosphate Mineral kapundaite naca fe3 4 po4 4 oh 3 5 h2o using sem edx and vibrational spectroscopic methods
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014Co-Authors: Ray L Frost, Andres Lopez, Ricardo ScholzAbstract:Abstract Vibrational spectroscopy enables subtle details of the molecular structure of kapundaite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. Kapundaite is the Fe 3+ member of the wardite group. The infrared and Raman spectroscopy were applied to compare the structure of kapundaite with wardite. The Raman spectrum of kapundaite in the 800–1400 cm −1 spectral range shows two intense bands at 1089 and 1114 cm −1 assigned to the ν 1 PO 4 3 - symmetric stretching vibrations. The observation of two bands provides evidence for the non-equivalence of the Phosphate units in the kapundaite structure. The infrared spectrum of kapundaite in the 500–1300 cm −1 shows much greater complexity than the Raman spectrum. Strong infrared bands are found at 966, 1003 and 1036 cm −1 and are attributed to the ν 1 PO 4 3 - symmetric stretching mode and ν 3 PO 4 3 - antisymmetric stretching mode. Raman bands in the ν 4 out of plane bending modes of the PO 4 3 - unit support the concept of non-equivalent Phosphate units in the kapundaite structure. In the 2600–3800 cm −1 spectral range, Raman bands for kapundaite are found at 2905, 3151, 3311, 3449 and 3530 cm −1 . These bands are broad and are assigned to OH stretching vibrations. Broad infrared bands are also found at 2904, 3105, 3307, 3453 and 3523 cm −1 and are attributed to water. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of kapundaite to be ascertained and compared with that of other Phosphate Minerals.
Ricardo Scholz - One of the best experts on this subject based on the ideXlab platform.
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a vibrational spectroscopic study of the Phosphate Mineral vantasselite al4 po4 3 oh 3 9h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Andres Lopez, Frederick L TheissAbstract:We have studied the Phosphate Mineral vantasselite Al4(PO4)3(OH)3·9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027cm−1 are assigned to the PO43−ν1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the Phosphate units in the vantasselite structure. Raman bands at 1051, 1076 and 1090cm−1 are attributed to the PO43−ν3 antisymmetric stretching vibration. A comparison is made with the spectroscopy of wardite. Strong infrared bands at 1044, 1078, 1092, 1112, 1133, 1180 and 1210cm−1 are attributed to the PO43−ν3 antisymmetric stretching mode. Some of these bands may be due to δAl2OH deformation modes. Vibrational spectroscopy offers a mechanism for the study of the molecular structure of vantasselite.
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a vibrational spectroscopic study of the anhydrous Phosphate Mineral sidorenkite na3mn po4 co3
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Fernanda Maria BelottiAbstract:Sidorenkite is a very rare low-temperature hydrothermal Mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a Phosphate–carbonate of sodium and manganese. Such a formula with two oxyanions lends itself to vibrational spectroscopy. The sharp Raman band at 959 cm−1 and 1012 cm−1 are assigned to the PO43− stretching modes, whilst the Raman bands at 1044 cm−1 and 1074 cm−1 are attributed to the CO32− stretching modes. It is noted that no Raman bands at around 800 cm−1 for sidorenkite were observed. The infrared spectrum of sidorenkite shows a quite intense band at 868 cm−1 with other resolved component bands at 850 and 862 cm−1. These bands are ascribed to the CO32− out-of-plane bend (ν2) bending mode. The series of Raman bands at 622, 635, 645 and 704 cm−1 are assigned to the ν4 Phosphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the carbonate anion from D3h or even C2v.
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a raman and infrared spectroscopic analysis of the Phosphate Mineral wardite naal3 po4 2 oh 4 2 h2o from brazil
Science & Engineering Faculty, 2014Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Cristiano LanaAbstract:Abstract A wardite Mineral sample from Lavra Da Ilha, Minas Gerais, Brazil has been examined by vibrational spectroscopy. The Mineral is unusual in that it belongs to a unique symmetry class, namely the tetragonal-trapezohedral group. The structure of wardite contains layers of corner-linked –OH bridged MO6 octahedra stacked along the tetragonal C-axis in a four-layer sequence and linked by PO4 groups. Consequentially not all Phosphate units are identical. Two intense Raman bands observed at 995 and 1051 cm−1 are assigned to the ν1 PO 4 3 - symmetric stretching mode. Intense Raman bands are observed at 605 and 618 cm−1 with shoulders at 578 and 589 cm−1 are assigned to the ν4 out of plane bending modes of the PO 4 3 - . The observation of multiple bands supports the concept of non-equivalent Phosphate units in the structure. Sharp infrared bands are observed at 3544 and 3611 cm−1 are attributed to the OH stretching vibrations of the hydroxyl units. Vibrational spectroscopy enables subtle details of the molecular structure of wardite to be determined.
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a vibrational spectroscopic study of the Phosphate Mineral whiteite camn mg2al2 po4 4 oh 2 8 h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014Co-Authors: Ray L Frost, Ricardo Scholz, Andres LopezAbstract:Vibrational spectroscopy enables subtle details of the molecular structure of whiteite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. The infrared and Raman spectroscopy were applied to compare the molecular structure of whiteite with that of other Phosphate Minerals. The Raman spectrum of whiteite shows an intense band at 972 cm(-1) assigned to the ν1PO4(3-) symmetric stretching vibrations. The low intensity Raman bands at 1076 and 1173 cm(-1) are assigned to the ν3PO4(3-) antisymmetric stretching modes. The Raman bands at 1266, 1334 and 1368 cm(-1) are assigned to AlOH deformation modes. The infrared band at 967 cm(-1) is ascribed to the PO4(3-)ν1 symmetric stretching vibrational mode. The infrared bands at 1024, 1072, 1089 and 1126 cm(-1) are attributed to the PO4(3-)ν3 antisymmetric stretching vibrations. Raman bands at 553, 571 and 586 cm(-1) are assigned to the ν4 out of plane bending modes of the PO4(3-) unit. Raman bands at 432, 457, 479 and 500 cm(-1) are attributed to the ν2 PO4 and H2PO4 bending modes. In the 2600 to 3800 cm(-1) spectral range, Raman bands for whiteite are found 3426, 3496 and 3552 cm(-1) are assigned to AlOH stretching vibrations. Broad infrared bands are also found at 3186 cm(-1). Raman bands at 2939 and 3220 cm(-1) are assigned to water stretching vibrations. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of whiteite to be ascertained and compared with that of other Phosphate Minerals.
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a study of the Phosphate Mineral kapundaite naca fe3 4 po4 4 oh 3 5 h2o using sem edx and vibrational spectroscopic methods
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014Co-Authors: Ray L Frost, Andres Lopez, Ricardo ScholzAbstract:Abstract Vibrational spectroscopy enables subtle details of the molecular structure of kapundaite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. Kapundaite is the Fe 3+ member of the wardite group. The infrared and Raman spectroscopy were applied to compare the structure of kapundaite with wardite. The Raman spectrum of kapundaite in the 800–1400 cm −1 spectral range shows two intense bands at 1089 and 1114 cm −1 assigned to the ν 1 PO 4 3 - symmetric stretching vibrations. The observation of two bands provides evidence for the non-equivalence of the Phosphate units in the kapundaite structure. The infrared spectrum of kapundaite in the 500–1300 cm −1 shows much greater complexity than the Raman spectrum. Strong infrared bands are found at 966, 1003 and 1036 cm −1 and are attributed to the ν 1 PO 4 3 - symmetric stretching mode and ν 3 PO 4 3 - antisymmetric stretching mode. Raman bands in the ν 4 out of plane bending modes of the PO 4 3 - unit support the concept of non-equivalent Phosphate units in the kapundaite structure. In the 2600–3800 cm −1 spectral range, Raman bands for kapundaite are found at 2905, 3151, 3311, 3449 and 3530 cm −1 . These bands are broad and are assigned to OH stretching vibrations. Broad infrared bands are also found at 2904, 3105, 3307, 3453 and 3523 cm −1 and are attributed to water. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of kapundaite to be ascertained and compared with that of other Phosphate Minerals.
Andres Lopez - One of the best experts on this subject based on the ideXlab platform.
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a vibrational spectroscopic study of the Phosphate Mineral vantasselite al4 po4 3 oh 3 9h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Andres Lopez, Frederick L TheissAbstract:We have studied the Phosphate Mineral vantasselite Al4(PO4)3(OH)3·9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027cm−1 are assigned to the PO43−ν1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the Phosphate units in the vantasselite structure. Raman bands at 1051, 1076 and 1090cm−1 are attributed to the PO43−ν3 antisymmetric stretching vibration. A comparison is made with the spectroscopy of wardite. Strong infrared bands at 1044, 1078, 1092, 1112, 1133, 1180 and 1210cm−1 are attributed to the PO43−ν3 antisymmetric stretching mode. Some of these bands may be due to δAl2OH deformation modes. Vibrational spectroscopy offers a mechanism for the study of the molecular structure of vantasselite.
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a vibrational spectroscopic study of the anhydrous Phosphate Mineral sidorenkite na3mn po4 co3
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Fernanda Maria BelottiAbstract:Sidorenkite is a very rare low-temperature hydrothermal Mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a Phosphate–carbonate of sodium and manganese. Such a formula with two oxyanions lends itself to vibrational spectroscopy. The sharp Raman band at 959 cm−1 and 1012 cm−1 are assigned to the PO43− stretching modes, whilst the Raman bands at 1044 cm−1 and 1074 cm−1 are attributed to the CO32− stretching modes. It is noted that no Raman bands at around 800 cm−1 for sidorenkite were observed. The infrared spectrum of sidorenkite shows a quite intense band at 868 cm−1 with other resolved component bands at 850 and 862 cm−1. These bands are ascribed to the CO32− out-of-plane bend (ν2) bending mode. The series of Raman bands at 622, 635, 645 and 704 cm−1 are assigned to the ν4 Phosphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the carbonate anion from D3h or even C2v.
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a raman and infrared spectroscopic analysis of the Phosphate Mineral wardite naal3 po4 2 oh 4 2 h2o from brazil
Science & Engineering Faculty, 2014Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Cristiano LanaAbstract:Abstract A wardite Mineral sample from Lavra Da Ilha, Minas Gerais, Brazil has been examined by vibrational spectroscopy. The Mineral is unusual in that it belongs to a unique symmetry class, namely the tetragonal-trapezohedral group. The structure of wardite contains layers of corner-linked –OH bridged MO6 octahedra stacked along the tetragonal C-axis in a four-layer sequence and linked by PO4 groups. Consequentially not all Phosphate units are identical. Two intense Raman bands observed at 995 and 1051 cm−1 are assigned to the ν1 PO 4 3 - symmetric stretching mode. Intense Raman bands are observed at 605 and 618 cm−1 with shoulders at 578 and 589 cm−1 are assigned to the ν4 out of plane bending modes of the PO 4 3 - . The observation of multiple bands supports the concept of non-equivalent Phosphate units in the structure. Sharp infrared bands are observed at 3544 and 3611 cm−1 are attributed to the OH stretching vibrations of the hydroxyl units. Vibrational spectroscopy enables subtle details of the molecular structure of wardite to be determined.
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a vibrational spectroscopic study of the Phosphate Mineral whiteite camn mg2al2 po4 4 oh 2 8 h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014Co-Authors: Ray L Frost, Ricardo Scholz, Andres LopezAbstract:Vibrational spectroscopy enables subtle details of the molecular structure of whiteite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. The infrared and Raman spectroscopy were applied to compare the molecular structure of whiteite with that of other Phosphate Minerals. The Raman spectrum of whiteite shows an intense band at 972 cm(-1) assigned to the ν1PO4(3-) symmetric stretching vibrations. The low intensity Raman bands at 1076 and 1173 cm(-1) are assigned to the ν3PO4(3-) antisymmetric stretching modes. The Raman bands at 1266, 1334 and 1368 cm(-1) are assigned to AlOH deformation modes. The infrared band at 967 cm(-1) is ascribed to the PO4(3-)ν1 symmetric stretching vibrational mode. The infrared bands at 1024, 1072, 1089 and 1126 cm(-1) are attributed to the PO4(3-)ν3 antisymmetric stretching vibrations. Raman bands at 553, 571 and 586 cm(-1) are assigned to the ν4 out of plane bending modes of the PO4(3-) unit. Raman bands at 432, 457, 479 and 500 cm(-1) are attributed to the ν2 PO4 and H2PO4 bending modes. In the 2600 to 3800 cm(-1) spectral range, Raman bands for whiteite are found 3426, 3496 and 3552 cm(-1) are assigned to AlOH stretching vibrations. Broad infrared bands are also found at 3186 cm(-1). Raman bands at 2939 and 3220 cm(-1) are assigned to water stretching vibrations. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of whiteite to be ascertained and compared with that of other Phosphate Minerals.
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a study of the Phosphate Mineral kapundaite naca fe3 4 po4 4 oh 3 5 h2o using sem edx and vibrational spectroscopic methods
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014Co-Authors: Ray L Frost, Andres Lopez, Ricardo ScholzAbstract:Abstract Vibrational spectroscopy enables subtle details of the molecular structure of kapundaite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. Kapundaite is the Fe 3+ member of the wardite group. The infrared and Raman spectroscopy were applied to compare the structure of kapundaite with wardite. The Raman spectrum of kapundaite in the 800–1400 cm −1 spectral range shows two intense bands at 1089 and 1114 cm −1 assigned to the ν 1 PO 4 3 - symmetric stretching vibrations. The observation of two bands provides evidence for the non-equivalence of the Phosphate units in the kapundaite structure. The infrared spectrum of kapundaite in the 500–1300 cm −1 shows much greater complexity than the Raman spectrum. Strong infrared bands are found at 966, 1003 and 1036 cm −1 and are attributed to the ν 1 PO 4 3 - symmetric stretching mode and ν 3 PO 4 3 - antisymmetric stretching mode. Raman bands in the ν 4 out of plane bending modes of the PO 4 3 - unit support the concept of non-equivalent Phosphate units in the kapundaite structure. In the 2600–3800 cm −1 spectral range, Raman bands for kapundaite are found at 2905, 3151, 3311, 3449 and 3530 cm −1 . These bands are broad and are assigned to OH stretching vibrations. Broad infrared bands are also found at 2904, 3105, 3307, 3453 and 3523 cm −1 and are attributed to water. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of kapundaite to be ascertained and compared with that of other Phosphate Minerals.
Fernanda Maria Belotti - One of the best experts on this subject based on the ideXlab platform.
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a vibrational spectroscopic study of the Phosphate Mineral vantasselite al4 po4 3 oh 3 9h2o
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Andres Lopez, Frederick L TheissAbstract:We have studied the Phosphate Mineral vantasselite Al4(PO4)3(OH)3·9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027cm−1 are assigned to the PO43−ν1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the Phosphate units in the vantasselite structure. Raman bands at 1051, 1076 and 1090cm−1 are attributed to the PO43−ν3 antisymmetric stretching vibration. A comparison is made with the spectroscopy of wardite. Strong infrared bands at 1044, 1078, 1092, 1112, 1133, 1180 and 1210cm−1 are attributed to the PO43−ν3 antisymmetric stretching mode. Some of these bands may be due to δAl2OH deformation modes. Vibrational spectroscopy offers a mechanism for the study of the molecular structure of vantasselite.
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a vibrational spectroscopic study of the anhydrous Phosphate Mineral sidorenkite na3mn po4 co3
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Fernanda Maria BelottiAbstract:Sidorenkite is a very rare low-temperature hydrothermal Mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a Phosphate–carbonate of sodium and manganese. Such a formula with two oxyanions lends itself to vibrational spectroscopy. The sharp Raman band at 959 cm−1 and 1012 cm−1 are assigned to the PO43− stretching modes, whilst the Raman bands at 1044 cm−1 and 1074 cm−1 are attributed to the CO32− stretching modes. It is noted that no Raman bands at around 800 cm−1 for sidorenkite were observed. The infrared spectrum of sidorenkite shows a quite intense band at 868 cm−1 with other resolved component bands at 850 and 862 cm−1. These bands are ascribed to the CO32− out-of-plane bend (ν2) bending mode. The series of Raman bands at 622, 635, 645 and 704 cm−1 are assigned to the ν4 Phosphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the carbonate anion from D3h or even C2v.
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assessment of the molecular structure of natrodufrenite nafe2 fe53 po4 4 oh 6 2 h2o a secondary pegmatite Phosphate Mineral from minas gerais brazil
Journal of Molecular Structure, 2013Co-Authors: Andres Lopez, Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Erika RibeiroAbstract:Abstract The Mineral natrodufrenite a secondary pegmatite Phosphate Mineral from Minas Gerais, Brazil, has been studied by a combination of scanning electron microscopy and vibrational spectroscopic techniques. Electron probe analysis shows the formula of the studied Mineral as (Na 0.88 Ca 0.12 ) ∑1.00 ( Fe 0.72 2 + Mn 0.11 Mg 0.08 Ca 0.04 Zr 0.01 Cu 0.01 ) ∑0.97 ( Fe 4.89 3 + Al 0.02 ) ∑4.91 (PO 4 ) 3.96 (OH 6.15 F 0.07 ) 6.22 ⋅2.05(H 2 O). Raman spectroscopy identifies an intense peak at 1003 cm −1 assigned to the PO 4 3 - ν 1 symmetric stretching mode. Raman bands are observed at 1059 and 1118 cm −1 and are attributed to the PO 4 3 - ν 3 antisymmetric stretching vibrations. A comparison is made with the spectral data of other hydrate hydroxy Phosphate Minerals including cyrilovite and wardite. Raman bands at 560, 582, 619 and 668 cm −1 are assigned to the ν 4 PO 4 3 - bending modes and Raman bands at 425, 444, 477 and 507 cm −1 are due to the ν 2 PO 4 3 - bending modes. Raman bands in the 2600–3800 cm −1 spectral range are attributed to water and OH stretching vibrations. Vibrational spectroscopy enables aspects of the molecular structure of natrodufrenite to be assessed.
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sem edx raman and infrared spectroscopic characterization of the Phosphate Mineral frondelite mn2 fe3 4 po4 3 oh 5
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2013Co-Authors: Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Martina BeganovicAbstract:Abstract We have analyzed a frondelite Mineral sample from the Cigana mine, located in the municipality of Conselheiro Pena, a well-known pegmatite in Brazil. In the Cigana pegmatite, secondary Phosphates, namely eosphorite, fairfieldite, fluorapatite, frondelite, gormanite, hureaulite, lithiophilite, reddingite and vivianite are common Minerals in miarolitic cavities and in massive blocks after triphylite. The chemical formula was determined as (Mn0.68, Fe0.32)(Fe3+)3,72(PO4)3.17(OH)4.99. The structure of the Mineral was assessed using vibrational spectroscopy. Bands attributed to the stretching and bending modes of PO 4 3 - and HOPO 3 3 - units were identified. The observation of multiple bands supports the concept of symmetry reduction of the Phosphate anion in the frondelite structure. Sharp Raman and infrared bands at 3581 cm−1 is assigned to the OH stretching vibration. Broad Raman bands at 3063, 3529 and 3365 cm−1 are attributed to water stretching vibrational modes.
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vibrational spectroscopic characterization of the Phosphate Mineral hureaulite mn fe 5 po4 2 hpo4 2 4 h2o
Science & Engineering Faculty, 2013Co-Authors: Ray L Frost, Ricardo Scholz, Andres Lopez, Fernanda Maria BelottiAbstract:This research was done on hureaulite samples from the Cigana claim, a lithium bearing pegmatite with triphylite and spodumene. The mine is located in Conselheiro Pena, east of Minas Gerais. Chemical analysis was carried out by Electron Microprobe analysis and indicated a manganese rich phase with partial substitution of iron. The calculated chemical formula of the studied sample is: (Mn3.23, Fe1.04, Ca0.19, Mg0.13)(PO4)2.7(HPO4)2.6(OH)4.78. The Raman spectrum of hureaulite is dominated by an intense sharp band at 959 cm−1 assigned to PO stretching vibrations of HPO42− units. The Raman band at 989 cm−1 is assigned to the PO43− stretching vibration. Raman bands at 1007, 1024, 1047, and 1083 cm−1 are attributed to both the HOP and PO antisymmetric stretching vibrations of HPO42− and PO43− units. A set of Raman bands at 531, 543, 564 and 582 cm−1 are assigned to the ν4 bending modes of the HPO42− and PO43− units. Raman bands observed at 414, and 455 cm−1 are attributed to the ν2 HPO42− and PO43− units. The intense A series of Raman and infrared bands in the OH stretching region are assigned to water stretching vibrations. Based upon the position of these bands hydrogen bond distances are calculated. Hydrogen bond distances are short indicating very strong hydrogen bonding in the hureaulite structure. A combination of Raman and infrared spectroscopy enabled aspects of the molecular structure of the Mineral hureaulite to be understood.
Martina Beganovic - One of the best experts on this subject based on the ideXlab platform.
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sem edx raman and infrared spectroscopic characterization of the Phosphate Mineral frondelite mn2 fe3 4 po4 3 oh 5
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2013Co-Authors: Ray L Frost, Ricardo Scholz, Fernanda Maria Belotti, Martina BeganovicAbstract:Abstract We have analyzed a frondelite Mineral sample from the Cigana mine, located in the municipality of Conselheiro Pena, a well-known pegmatite in Brazil. In the Cigana pegmatite, secondary Phosphates, namely eosphorite, fairfieldite, fluorapatite, frondelite, gormanite, hureaulite, lithiophilite, reddingite and vivianite are common Minerals in miarolitic cavities and in massive blocks after triphylite. The chemical formula was determined as (Mn0.68, Fe0.32)(Fe3+)3,72(PO4)3.17(OH)4.99. The structure of the Mineral was assessed using vibrational spectroscopy. Bands attributed to the stretching and bending modes of PO 4 3 - and HOPO 3 3 - units were identified. The observation of multiple bands supports the concept of symmetry reduction of the Phosphate anion in the frondelite structure. Sharp Raman and infrared bands at 3581 cm−1 is assigned to the OH stretching vibration. Broad Raman bands at 3063, 3529 and 3365 cm−1 are attributed to water stretching vibrational modes.
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vibrational spectroscopy of the Phosphate Mineral lazulite mg fe al2 po4 2 oh 2 found in the minas gerais brazil
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2013Co-Authors: Ray L Frost, Fernanda Maria Belotti, Martina Beganovic, Ricardo ScholzAbstract:This research was done on lazulite samples from the Gentil mine, a lithium bearing pegmatite located in the municipality of Mendes Pimentel, Minas Gerais, Brazil. Chemical analysis was carried out by electron microprobe analysis and indicated a magnesium rich phase with partial substitution of iron. Traces of Ca and Mn, (which partially replaced Mg) were found. The calculated chemical formula of the studied sample is: (Mg0.88 ,F e 0.11)Al1.87(PO4)2.08(OH)2.02. The Raman spectrum of lazulite is dominated by an intense sharp band at 1060 cm � 1 assigned to PO stretching vibrations of of tetrahedral [PO4] clusters presents into the