A contribution to the infrared spectrum of the metaborate ion BO′2 isolated in the alkali halide lattice

A vibrational spectroscopic study of the borate mineral takedaite Ca3(BO3)2

We have studied the mineral takedaite Ca3(BO3)2, a borate mineral of calcium using SEM with EDX and vibrational spectroscopy. Chemical analysis shows a homogeneous phase, composed of Ca. Boron was not detected. A very intense Raman band at 1087 cm(-1) is assigned to the BO stretching vibration of BO3 units. Additional Raman bands may be due to isotopic splitting. In the infrared spectrum, bands at 1218 cm(-1) and at 1163, 1262 and 1295 cm(-1) are assigned to the trigonal borate stretching modes. Raman bands at 712 and 715 cm(-1) are assigned to the in-plane bending modes of the BO3 units. Vibrational spectroscopy enables aspects of the molecular structure of takedaite to be assessed.

The molecular structure of the borate mineral inderite Mg(H4B3O7)(OH) · 5H2O--a vibrational spectroscopic study

We have undertaken a study of the mineral inderite Mg(H4B3O7)(OH) · 5H2O a hydrated hydroxy borate mineral of magnesium using scanning electron microscopy, thermogravimetry and vibrational spectroscopic techniques. The structure consists of [Formula: see text] soroborate groups and Mg(OH)2(H2O)4 octahedra interconnected into discrete molecules by the sharing of two OH groups. Thermogravimetry shows a mass loss of 47.2% at 137.5 °C, proving the mineral is thermally unstable. Raman bands at 954, 1047 and 1116 cm(-1) are assigned to the trigonal symmetric stretching mode. The two bands at 880 and 916 cm(-1) are attributed to the symmetric stretching mode of the tetrahedral boron. Both the Raman and infrared spectra of inderite show complexity. Raman bands are observed at 3052, 3233, 3330, 3392 attributed to water stretching vibrations and 3459 cm(-1) with sharper bands at 3459, 3530 and 3562 cm(-1) assigned to OH stretching vibrations. Vibrational spectroscopy is used to assess the molecular structure of inderite.

Vibrational spectroscopy of the borate mineral gaudefroyite Ca4MN3+3-x (BO3)3(CO3) (O, OH). from N'Chwaning II mine, Kalahari, Republic of South Africa

Gaudefroyite Ca4MN3+3-x (BO3)3(CO3) (O, OH)3 is an unusual mineral containing both borate and carbonate groups and is found in the oxidation zones of manganese minerals, and it is black in color. Vibrational spectroscopy has been used to explore the molecular structure of gaudefroyite. Gaudefroyite crystals are short dipyramidal or prismatic with prominent pyramidal terminations, to 5 cm. Two very sharp Raman bands at 927 and 1076 cm(-1) are assigned to trigonal borate and carbonate respectively. Broad Raman bands at 1194, 1219 and 1281 cm(-1) are attributed to BOH in-plane bending modes. Raman bands at 649 and 670 cm(-1) are assigned to the bending modes of trigonal and tetrahedral boron. Infrared spectroscopy supports these band assignments. Raman bands in the OH stretching region are of a low intensity. The combination of Raman and infrared spectroscopy enables the assessment of the molecular structure of gaudefroyite to be made.

Vibrational spectroscopy of the borate mineral chambersite MnB7O13Cl--implications for the molecular structure

Chambersite is a manganese borate mineral with formula: MnB7O13Cl and occurs as colorless crystals in the monoclinic pyramidal crystal system. Raman bands at 902, 920, 942 and 963 cm(-1) are assigned to the BO stretching vibration of the B7O13 units. Raman bands at 1027, 1045, 1056, 1075 and 1091 cm(-1) are attributed to the BCl in-plane bending modes. The intense infrared band at 866 cm(-1) is assigned to the trigonal borate stretching modes. The Raman band at 660 cm(-1) together with bands at 597, 642 679, 705 and 721 cm(-1) are assigned to the trigonal and tetrahedral borate bending modes. The molecular structure of a natural chambersite has been assessed using vibrational spectroscopy.

Vibrational spectroscopy of the mineral meyerhofferite CaB3O3(OH)5·H2O--an assessment of the molecular structure

Meyerhofferite is a calcium hydrated borate mineral with ideal formula: CaB3O3(OH)5·H2O and occurs as white complex acicular to crude crystals with length up to ~4 cm, in fibrous divergent, radiating aggregates or reticulated and is often found in sedimentary or lake-bed borate deposits. The Raman spectrum of meyerhofferite is dominated by intense sharp band at 880 cm(-1) assigned to the symmetric stretching mode of trigonal boron. Broad Raman bands at 1046, 1110, 1135 and 1201 cm(-1) are attributed to BOH in-plane bending modes. Raman bands in the 900-1000 cm(-1) spectral region are assigned to the antisymmetric stretching of tetrahedral boron. Distinct OH stretching Raman bands are observed at 3400, 3483 and 3608 cm(-1). The mineral meyerhofferite has a distinct Raman spectrum which is different from the spectrum of other borate minerals, making Raman spectroscopy a very useful tool for the detection of meyerhofferite in sedimentary and lake bed deposits.

Assessment of the molecular structure of the borate mineral sakhaite Ca12Mg4(BO3)7(CO3)4Cl(OH)2·H2O using vibrational spectroscopy

The structure of the borate mineral sakhaite Ca(12)Mg(4)(BO(3))(7)(CO(3))(4)Cl(OH)(2)·H(2)O, a borate-carbonate of calcium and magnesium has been assessed using vibrational spectroscopy. Assignment of bands is undertaken by comparison with the data from other published results. Intense Raman band at 1134 cm(-1) with a shoulder at 1123 cm(-1) is assigned to the CO(3)(2-) symmetric stretching mode. The Raman spectrum displays bands at 1479, 1524 and 1560 cm(-1) which are assigned to the CO(3)(2-) antisymmetric stretching vibrations. The observation of multiple carbonate stretching bands supports the concept that the carbonate units are non-equivalent. The Raman band at 968 cm(-1) with a shoulder at 950 cm(-1) is assigned to the symmetric stretching mode of trigonal boron. Raman bands at 627 and 651 cm(-1) are assigned to the out-of-plane bending modes of trigonal and tetrahedral boron. Raman spectroscopy coupled with infrared spectroscopy enables the molecular structure of the mineral sakhaite to be assessed.

Assessment of the molecular structure of the borate mineral boracite Mg3B7O13Cl using vibrational spectroscopy

Boracite is a magnesium borate mineral with formula: Mg(3)B(7)O(13)Cl and occurs as blue green, colorless, gray, yellow to white crystals in the orthorhombic - pyramidal crystal system. An intense Raman band at 1009 cm(-1) was assigned to the BO stretching vibration of the B(7)O(13) units. Raman bands at 1121, 1136, 1143 cm(-1) are attributed to the in-plane bending vibrations of trigonal boron. Four sharp Raman bands observed at 415, 494, 621 and 671 cm(-1) are simply defined as trigonal and tetrahedral borate bending modes. The Raman spectrum clearly shows intense Raman bands at 3405 and 3494 cm(-1), thus indicating that some Cl anions have been replaced with OH units. The molecular structure of a natural boracite has been assessed by using vibrational spectroscopy.

Raman spectroscopy of the borate mineral ameghinite NaB3O3(OH)4

The molecular structure of the sodium borate mineral ameghinite NaB(3)O(3)(OH)(4) has been determined by the use of vibrational spectroscopy. The crystal structure consists of isolated [B(3)O(3)(OH)(4)](-) units formed by one tetrahedron and two triangles. H bonds and Na atoms link these polyanions to form a three-dimensional framework. The Raman spectrum is dominated by an intense band at 1027 cm(-1), attributed to BO stretching vibrations of both the trigonal and tetrahedral boron. A series of Raman bands at 1213, 1245 and 1281 cm(-1) are ascribed to BOH in-plane bending modes. The infrared spectra are characterized by strong overlap of broad multiple bands. An intense Raman band found at 620 cm(-1) is attributed to the bending modes of trigonal and tetrahedral boron. Multiple Raman bands in the OH stretching region are observed at 3206, 3249 and 3385 cm(-1). Raman spectroscopy coupled with infrared spectroscopy has enabled aspects about the molecular structure of the borate mineral ameghinite to be assessed.