The structural morphology of aragonite
Heijnen, Wim M. M.
Neues Jahrbuch für Mineralogie - Abhandlungen Band 154 Heft 3 (1986), p. 223 - 245
35 références bibliographiques
publié: Jul 14, 1986
DOI: 10.1127/njma/154/1986/223
ArtNo. ESP154015403001, Prix: 29.00 €
Abstract
The application of Hartman & Perdok’s PBC theory to the aragonite structure results in seven F forms: [011], [110], [020], [111], [002], [102] and [112]. For some forms several F slice configurations are possible. For a quantitative derivation of the theoretical growth morphology electrostatic attachment energies are calculated for three different charge distribution models: C-2O30, C+1O3-1 and C+43-2.The behaviour of the attachment energy as a function of the charge on the oxygen atoms varies considerably for the different F forms. The growth forms are constructed from the attachment energies, taken directly proportional to the relative growth rates. The growth morphology strongly depends upon both the charge distribution and the assumed growth mechanism of the [011] form, which grows via layers having thickness either d011 or 1/2d011. The inclusion of corrections for repulsion and dispersion energy in the calculated attachment energies does not change the theoretical growth forms, because both terms cancel out.
Mots-clefs
Aragonite • morphology • PBC theory