Coordination of boron in nominally boron-free rock forming silicates: Evidence for incorporation of BO3 groups in clinopyroxene

Identification of hydrogen defects linked to boron substitution in synthetic forsterite and natural olivine

“…They occur in a frequency range where asymmetric n 3 vibration modes of BO 3 groups are generally active (Weir and Schroeder 1964), which suggests the occurrence of BO 3 groups subparallel to the (x,z) plane. Considering the previously reported replacement of SiO 4 tetrahedra by BO 3 groups in synthetic anhydrous diopside and forsterite (Halenius et al 2010a(Halenius et al , 2010b, it is likely that BO 3 groups also occur in forsterite (the n 3 bands in diopside are shifted to higher frequencies (>1300 cm -1 ) due to the occurrence of B-O-Si linkages in the tetrahedral chains). The bands at 1167 and 1256 cm -1 in the forsterite spectra are similar to those at 1164 and 1257 cm -1 in the B-rich olivine from the Tayozhnoye deposit (Sykes et al 1994).…”

The split network analysis for exploring composition–structure correlations in multi-component glasses: II. Multinuclear NMR studies of alumino-borosilicates and glass-wool fibers

“…Fig. 3 displays 11 B NMR spectra of the various samples, revealing two distinct NMR resonances: a primary sharp peak at − 1.4 ppm, assigned to B [4] coordinations, and a significantly broader signal, which is typical for the less symmetric planar B [3] units [25,34,[43][44][45]. Fig.…”

A nuclear geochemical analysis system for boron quantification using a focused ion beam

“…In many cases, depth profiling of these light isotopes is also possible and then either the resonant behavior or stopping effects can be utilized. The nuclear reaction, on which the NRA analysis of boron presented in this work is based, is the reaction [12], i.e. where a 11 B nucleus in the sample reacts with a proton of the incoming particle beam, resulting in the production of three alpha particles.…”

“…The main tool of this rather extensive boron program has been the nuclear reaction [12], utilizing a beam energy of just below 700 keV as the reaction has a broad resonance (300 mb at 660 keV) here. The three alpha particles emitted from the reaction can easily (as their energies are considerably higher than the elastically scattered incoming proton) be detected and counted as a function of the beam charge collected.…”