Rare earth element and gallium diffusion in yttrium aluminum garnet Export

@article{Cherniak1998, abstract = {Diffusion of four rare-earth elements and gallium has been measured in yttrium aluminum garnet (YAG). Sources of diffusant were mixtures of alumina and rare-earth element oxides for REE diffusion, and mixtures of gallium and yttrium oxides for Ga diffusion. Diffusion profiles were measured with Rutherford backscattering spectrometry (RBS). For the rare-earth elements investigated, the following Arrhenius relations were obtained: DLa=6.87\&\#5010-1 exp (-582\&\#4521 kJ mol-1 /RT) m2s-1 DNd=1.63\&\#5010-1 exp (-567\&\#4515 kJ mol-1 /RT) m2s-1 DDy=2.70\&\#50100 exp (-603\&\#4535 kJ mol-1 /RT) m2s-1 DYb=1.50\&\#5010-2 exp (-540\&\#4526 kJ mol-1 /RT) m2s-1 Diffusion rates for the rare earths are quite similar, in contrast with trends noted for zircon. It is likely that these differences are a consequence of the relative ionic radii of the REE and the cations for which they substitute in the mineral lattice. For gallium, the following Arrhenius relation was determined: DGa=9.96\&\#5010-6 exp (-404\&\#4519 kJ mol-1 /RT) m2s-1 Gallium diffuses faster than the REE in YAG and has a smaller activation energy for diffusion. These data mirror relative trends in diffusion rates for YIG, in which trivalent cations occupying tetrahedral and octahedral sites (i.e., Al, Ga, Fe) diffuse faster than trivalent cations occupying dodecahedral sites (i.e., Y and the REE), and suggest that the rate-limiting process in the diffusion-controlled regime of solid-state creep of YAG is the diffusion of yttrium.}, author = {Cherniak, D. J.}, citeulike-article-id = {1531411}, citeulike-linkout-0 = {http://dx.doi.org/10.1007/s002690050172}, day = {12}, doi = {10.1007/s002690050172}, journal = {Physics and Chemistry of Minerals}, keywords = {diffusion, diffusion-p, dy, garnet, la, monocrystal, nd, yag, yb}, month = {December}, number = {2}, pages = {156--163}, posted-at = {2007-08-02 23:31:18}, priority = {0}, title = {Rare earth element and gallium diffusion in yttrium aluminum garnet}, url = {http://dx.doi.org/10.1007/s002690050172}, volume = {26}, year = {1998} }

TY - JOUR ID - Cherniak1998 L3 - citeulike-article-id:1531411 N2 - Diffusion of four rare-earth elements and gallium has been measured in yttrium aluminum garnet (YAG). Sources of diffusant were mixtures of alumina and rare-earth element oxides for REE diffusion, and mixtures of gallium and yttrium oxides for Ga diffusion. Diffusion profiles were measured with Rutherford backscattering spectrometry (RBS). For the rare-earth elements investigated, the following Arrhenius relations were obtained: DLa=6.87&#5010-1 exp (-582&#4521 kJ mol-1 /RT) m2s-1 DNd=1.63&#5010-1 exp (-567&#4515 kJ mol-1 /RT) m2s-1 DDy=2.70&#50100 exp (-603&#4535 kJ mol-1 /RT) m2s-1 DYb=1.50&#5010-2 exp (-540&#4526 kJ mol-1 /RT) m2s-1 Diffusion rates for the rare earths are quite similar, in contrast with trends noted for zircon. It is likely that these differences are a consequence of the relative ionic radii of the REE and the cations for which they substitute in the mineral lattice. For gallium, the following Arrhenius relation was determined: DGa=9.96&#5010-6 exp (-404&#4519 kJ mol-1 /RT) m2s-1 Gallium diffuses faster than the REE in YAG and has a smaller activation energy for diffusion. These data mirror relative trends in diffusion rates for YIG, in which trivalent cations occupying tetrahedral and octahedral sites (i.e., Al, Ga, Fe) diffuse faster than trivalent cations occupying dodecahedral sites (i.e., Y and the REE), and suggest that the rate-limiting process in the diffusion-controlled regime of solid-state creep of YAG is the diffusion of yttrium. IS - 2 JF - Physics and Chemistry of Minerals EP - 163 TI - Rare earth element and gallium diffusion in yttrium aluminum garnet VL - 26 SP - 156 KW - diffusion KW - diffusion-p KW - dy KW - garnet KW - la KW - monocrystal KW - nd KW - yag KW - yb AU - Cherniak, DJ PY - 1998/12/12/ UR - http://dx.doi.org/10.1007/s002690050172 ER -