First high-pressure synthesis of rossmanitic tourmaline and evidence for the incorporation of Li at the X site
First high-pressure synthesis of rossmanitic tourmaline and evidence for the incorporation of Li at the X site
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首次高压合成罗斯曼石碧玺以及 X 位点掺入锂的证据
DOI：
10.1007/s00269-016-0863-0
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发表时间：
2017
影响因子：
1.4
通讯作者：
Giester
中科院分区：
文献类型：
--
作者：
Kutzschbach;Wunder;Krstulovic;Trumbull;Rocholl;Giester
锂是某些电气石的重要成分，特别是在化学演化的花岗岩和伟晶岩中。迄今为止，合成富锂电气石的所有尝试都没有成功。本文描述了在4GPa和700 °C下在Li_2 O-Al_2 O_3-SiO_2-B_2 O_3-H_2 O（LASBH）系统中由无晶种的固体起始材料（由Li_2 O、γ-Al_2 O_3、石英和H_3BO_3的均匀混合物组成）首次合成rossmanitic tournament。在12天的运行持续时间之后的固体运行产物包含蔷薇辉石电气石（68wt%）、二钠镁矾（28wt%）和痕量的锂辉石（3wt%）和柯石英（1wt%）。电气石形成自形的大棱柱状晶体（30 × 100 μm），无包裹体，化学不分区。精细晶胞参数为：a= 15.7396（9）<$，c= 7.0575（5）<$，V= 1514.1（2）<$3。通常，Li+离子被假定为仅占据电气石结构中的八面体Y位点，最大为每分子式单位（pfu）2个Li。然而，通过电子微探针和二次离子质谱法测定的我们的合成电气石的化学组成得到式：X（Si0.67（11）Li0.33（11））Y（Al2.53（10）Li0.47（10））Z（Al 6）T（Si5.42（15）B0.58（15））O 18 B（BO 3）3V+W[（OH）2.40（3）O1.60（3）]，其中大量的Li占据X位点以满足电荷平衡要求。在偏振单晶拉曼光谱（例如单晶XRD结构精修）中OH伸缩振动的可靠归属证实了Li在X位点的掺入[分别为0.24（9）和0.15（5）XLi pfu]。SREF数据显示，Li-O 1距离显著缩短，以补偿Li+在X位点处与Na+、K+或Ca 2+相比较小的离子半径，即，Li更接近Si 6 O 18环，并与氧形成七重配位。
Lithium is an important component of some tourmalines, especially in chemically evolved granites and pegmatites. All attempts at synthesizing Li-rich tourmaline have so far been unsuccessful. Here we describe the first synthesis of rossmanitic tourmaline at 4 GPa and 700 °C in the system Li2O–Al2O3–SiO2–B2O3–H2O (LASBH) from seed-free solid starting materials consisting of a homogenous mixture of Li2O, γ-Al2O3, quartz and H3BO3. The solid run products after 12-day run duration comprise rossmanitic tourmaline (68 wt%), dumortierite (28 wt%) and traces of spodumene (3 wt%) and coesite (1 wt%). Tourmaline forms idiomorphic, large prismatic crystals (30 × 100 μm), which are inclusion free and chemically unzoned. The refined cell dimensions of the tourmaline are:a= 15.7396(9) Å,c= 7.0575(5) Å,V= 1514.1(2) Å3. Conventionally, the Li+ion is assumed to exclusively occupy the octahedral Y site in the tourmaline structure to a maximum of 2 Li per formula unit (pfu). However, the chemical composition of our synthetic tourmaline determined by electron microprobe and secondary ion mass spectroscopy results in the formula:X(☐0.67(11)Li0.33(11))Y(Al2.53(10)Li0.47(10))Z(Al6)T(Si5.42(15)B0.58(15))O18B(BO3)3V+W[(OH)2.40(3)O1.60(3)], wherein a significant amount of Li occupies the X site for charge balance requirements. Reliable assignment of the OH-stretching vibrations in a polarized single-crystal Raman spectrum such as a single-crystal XRD structure refinement, confirms the incorporation of Li at the X site [0.24(9) and 0.15(5)XLi pfu, respectively]. The SREF data show that the Li–O1 distances are shortened significantly in order to compensate for the smaller ionic radius of Li+compared to Na+, K+or Ca2+at the X site,i.e.,Li is closer to the Si6O18ring and to a sevenfold coordination with oxygen.
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影响因子：
3.1
作者：
Ertl, Andreas;Giester, Gerald;Rossman, George R.
通讯作者：
Rossman, George R.
影响因子：
3.5
作者：
Eleanor J. Berryman;B. Wunder;R. Wirth;D. Rhede;G. Schettler;G. Franz;W. Heinrich
通讯作者：
Eleanor J. Berryman;B. Wunder;R. Wirth;D. Rhede;G. Schettler;G. Franz;W. Heinrich
X位点空置铝电气石：一种新的合成端元
影响因子：
2.1
作者：
Ulrich Wodara;W. Schreyer
通讯作者：
W. Schreyer
Rossmanite，⃞(LiAl2)Al6(Si6O18)(BO3)3(OH)4，一种新型缺碱电气石：描述和晶体结构
影响因子：
3.1
作者：
Julie;B.;Selway;M. Novak;Frank;C.;Hawthorne;P. Černý;L. Ottolini;T.;K. Kyser
通讯作者：
K. Kyser
过量硼取代四面体位点硅的合成电气石（橄榄石）：II。
影响因子：
2.1
作者：
B. Marler;Markus Borowski;Ulrich Wodara;W. Schreyer
通讯作者：
W. Schreyer