Research output: Contribution to journal › Article › peer-review
Incorporation of 3d elements in tourmalines : Structural adjustments and stability. / Vereshchagin, Oleg S.; Frank-Kamenetskaya, Olga V.; Rozhdestvenskaya, Ira V.; Zolotarev, Anatoly A.
In: European Journal of Mineralogy, Vol. 30, No. 5, 01.09.2018, p. 917-928.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Incorporation of 3d elements in tourmalines
T2 - Structural adjustments and stability
AU - Vereshchagin, Oleg S.
AU - Frank-Kamenetskaya, Olga V.
AU - Rozhdestvenskaya, Ira V.
AU - Zolotarev, Anatoly A.
PY - 2018/9/1
Y1 - 2018/9/1
N2 - The crystal structure of 45 tourmalines containing trivalent cations (Me3+: Cr3+, V3+, Fe3+) and 43 tourmalines containing divalent cations (Me2+: Fe2+, Mn2+, Co2+, Ni2+, Cu2+) of 3d elements were analysed. We establish that the incorporation of Me3+ cations is controlled by the ratio between the sizes of YO6 and ZO(6) octahedra and does not exceed eight atoms per formula unit (apfu), while the incorporation of Me2+ cations is controlled by the charge balance and does not exceed 3 apfu. We prove that there are no structural constraints controlling the incorporation of Co, Ni and Cu cations into the tourmaline structure at concentrations of up to 1 apfu. We show that, when the limiting content (less or equal to 1 apfu and 1.6 apfu for divalent and trivalent cations, respectively) is reached, these cations start to occupy not only YO6, but also ZO(6) octahedra, to maintain stability of the crystal structure. As the content of 3d-element cations increases further, the degree of disorder grows and, at a content of similar to 7 apfu, their distribution is close to statistical. An increase in the content of 3d cations, accompanied by their disordering, causes a decrease in disparity between sizes of YO6 and ZO(6) octahedra and their deformations.
AB - The crystal structure of 45 tourmalines containing trivalent cations (Me3+: Cr3+, V3+, Fe3+) and 43 tourmalines containing divalent cations (Me2+: Fe2+, Mn2+, Co2+, Ni2+, Cu2+) of 3d elements were analysed. We establish that the incorporation of Me3+ cations is controlled by the ratio between the sizes of YO6 and ZO(6) octahedra and does not exceed eight atoms per formula unit (apfu), while the incorporation of Me2+ cations is controlled by the charge balance and does not exceed 3 apfu. We prove that there are no structural constraints controlling the incorporation of Co, Ni and Cu cations into the tourmaline structure at concentrations of up to 1 apfu. We show that, when the limiting content (less or equal to 1 apfu and 1.6 apfu for divalent and trivalent cations, respectively) is reached, these cations start to occupy not only YO6, but also ZO(6) octahedra, to maintain stability of the crystal structure. As the content of 3d-element cations increases further, the degree of disorder grows and, at a content of similar to 7 apfu, their distribution is close to statistical. An increase in the content of 3d cations, accompanied by their disordering, causes a decrease in disparity between sizes of YO6 and ZO(6) octahedra and their deformations.
KW - tourmaline
KW - structural adjustment
KW - crystal structure refinement
KW - crystal chemistry
KW - 3d elements
KW - SCHORL-DRAVITE SERIES
KW - MN2+ SITE OCCUPANCY
KW - CRYSTAL-STRUCTURE
KW - BEARING TOURMALINES
KW - MN2+-RICH TOURMALINE
KW - NICKELOAN TOURMALINE
KW - CHEMICAL-COMPOSITION
KW - RICH TOURMALINE
KW - SOLID-SOLUTIONS
KW - GOLD DEPOSIT
UR - http://www.scopus.com/inward/record.url?scp=85056568204&partnerID=8YFLogxK
U2 - 10.1127/ejm/2018/0030-2781
DO - 10.1127/ejm/2018/0030-2781
M3 - Article
AN - SCOPUS:85056568204
VL - 30
SP - 917
EP - 928
JO - European Journal of Mineralogy
JF - European Journal of Mineralogy
SN - 0935-1221
IS - 5
ER -
ID: 36107895