Inaug.-diss.--Leipzig. / Lebenslauf. "Separat-abdruck aus der Zeitschrift der Deutschen geologischen gesellschaft. Jahrgang 1910."

Inaug.-diss.--Leipzig. / Lebenslauf. "Separat-abdruck aus der Zeitschrift der Deutschen geologischen gesellschaft. Jahrgang 1910."

Electron microprobe analyses of 37 axinites substantiate the conclusions of Sanero and Gottardi (1968) as to the substitutional solid solution between octahedrally coordinated divalent cations Ca, Fe, and Mn. The analyses also suggest the substitution of Fe³⁺ for Al in the AlO₅(OH) octahedra for six axinites and the substitution of Al for Si in tetrahedral coordination for one specimen. The chemistry of the axinite group is best described by a new structural formula: [(Mn, Fe²⁺, Mg, Zn)(Ca_2-xMn_x)(Al_2-yFe_y³⁺)]₂^VI(OH)₂[(B₂Si₈_zAl_z)^IVO₃₀], where x < 1, y << 1, and z << 1. Pronounced layering approximately parallel to (lll), bands of B₂Si₈O₃₀ groups parallel to [011], and four types of octahedral chains influence indicatrix orientation, external morphology, and cleavage. Due to their proximity to octahedral chains, the b and c cell edges have high correlations with <r>, the mean radius of octahedral cations. Density and mean refractive index are shown to be highly correlated with the amount of transition metal oxides present for all axinites and 2Vα is highly correlated with Mg content for the non-zincian 2Ca-axinites. Reasonable estimates of composition can be obtained for the non-zincian 2Ca-axinites by using the following equations for the mole fraction of Mg, Fe, and Mn: Mg = -14.333 <R.I.>+ 0.012(2Vα) + 23.487 Fe= 71.937 <R.I.> - 11.810(p_obs) - 81.890 Mn = -42.903 <R.I.> + 12.523(p_obs) + 31.473. / Master of Science

New iron phosphate and borophosphate compounds were synthesized and characterized by single crystal/powder X-ray diffraction, infrared spectroscopy, raman spectroscopy, thermogravimetric analysis, electron microscopy and elemental analysis. Using several compositions, Fey B(PO4)x type of compounds were attempted to be prepared by solid state reactions. The solid state reactions of boron compounds with a phosphating agent has been completed at 950oC. A new product Fe2BP3O12 is synthesized and indexed in this work which is isostructural with Cr2 BP3O12 A single crystal of iron ammonium phosphate, (NH4)3-xHxFeP3O12, was synthesized by a hydrothermal method and characterized. Its X-ray powder diffraction pattern was indexed in orthorhombic system. The unit cell parameters were found to be as a = 7.775 (&Aring / ), b = 7.445(&Aring / ), c = 14.331(&Aring / ) The compound with the formula NH4FeBP2O8OH was synthesized by hydrothermal method. Its X-ray powder diffraction pattern was indexed in monoclinic system. The unit cell parameters were found to be a = 9.336, b = 8.278, c =9.642&Aring / , and &amp / #946 / = 101.60o, which are good agreement with the literature values. Ferro-axinite type of compound was discovered as single crystals resembling the axinite mineral. The compound was indexed in triclinic system with the unit cell parameters of a = 7.167, b = 8.840 , c = 9.455&Aring / , &amp / #945 / = 64.83o, &amp / #946 / = 64.83o, &amp / #947 / = 69.42o. A zeotype Fe(H2O)2BP2O8.H2O, which was obtained by hydrothermal methods before, was synthesized by a precipitation method using different initial reactant. In this case, instead of Fe+2, Fe+3 compound was used as a reactant. All the compounds have been investigated by FTIR spectroscopy and the assignments of the functional BO3, BO4 and PO4 groups have been done.