A single-crystal neutron diffraction study of hambergite, Be2BO3(OH,F)

Simple item page
dc.contributor.authorGatta, GDen_AU
dc.contributor.authorMcIntyre, GJen_AU
dc.contributor.authorBromiley, Gen_AU
dc.contributor.authorGuastoni, Aen_AU
dc.contributor.authorNestola, Fen_AU
dc.date.accessioned2014-03-07T04:51:16Zen_AU
dc.date.available2014-03-07T04:51:16Zen_AU
dc.date.issued2012-12-01en_AU
dc.date.statistics2014-03-07en_AU
dc.description.abstractThe crystal chemistry and crystal structure of hambergite from the Anjanabonoina mine, Madagascar [Be2BO3(OH)(0.96)F-0.04, Z = 8, a = 9.762(2), b = 12.201(2), c = 4.430(1) angstrom, V = 527.6(2) angstrom(3), space group Pbca], were reinvestigated by means of electron microprobe analysis in wavelength-dispersive mode, secondary-ion mass spectrometry, single-crystal X-ray and neutron Laue diffraction. Chemical analyses show only a small amount of F (0.7-0.8 wt%, approximately 0.04 atoms per formula unit) substituting OH and no other substituent at a significant level. An anisotropic neutron structural refinement has been performed with final agreement index R-1 = 0.0504 for 76 refined parameters and 1430 unique reflections with F-o>4 sigma(F-o). The geometry of the hydroxyl group and hydrogen bonding in hambergite is now well defined: (1) only one independent H site was located and the O4-H distance, corrected for "riding motion," is similar to 0.9929 angstrom; (2) only one hydrogen bond appears to be energetically favorable, with a symmetry-related O4 as acceptor and with O4 center dot center dot center dot O4 = 2.904(1) angstrom, H center dot center dot center dot O4 = 1.983(1) angstrom, and O4-H center dot center dot center dot O4 = 157.5(1)degrees. In other words, O4 sites act both as donor and as acceptor of the hydrogen bond, with a zigzag chain of H-bonds along [001]. The hydrogen-bonding scheme in hambergite found in this study is consistent with the pleochroic scheme of the infrared spectra previously reported, with two intensive modes ascribable to stretching vibrations of the hydroxyl group, at 3415 and 3520 cm(-1), respectively. The two modes suggest at least two distinct hydrogen-bonding environments, ascribable to the presence of oxygen and fluorine at the acceptor site. © 2012, Mineralogical Society of Americaen_AU
dc.identifier.citationGatta, G. D., McIntyre, G. J., Bromiley, G., Guastoni, A., & Nestola, F. (2012). A single-crystal neutron diffraction study of hambergite, Be2BO3(OH,F). American Mineralogist, 97(11-12), 1891-1897. doi:10.2138/am.2012.4232en_AU
dc.identifier.govdoc4566en_AU
dc.identifier.issn0003-004Xen_AU
dc.identifier.issue11-12en_AU
dc.identifier.journaltitleAmerican Mineralogisten_AU
dc.identifier.pagination1891-1897en_AU
dc.identifier.urihttp://dx.doi.org/10.2138/am.2012.4232en_AU
dc.identifier.urihttp://apo.ansto.gov.au/dspace/handle/10238/5249en_AU
dc.identifier.volume97en_AU
dc.language.isoenen_AU
dc.publisherDe Gruyteren_AU
dc.subjectCrystalsen_AU
dc.subjectChemistryen_AU
dc.subjectElectron microprobe analysisen_AU
dc.subjectWavelengthsen_AU
dc.subjectSpectroscopyen_AU
dc.subjectFluorineen_AU
dc.titleA single-crystal neutron diffraction study of hambergite, Be2BO3(OH,F)en_AU
dc.typeJournal Articleen_AU
Files
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Journal Articles