Flux Growth of [NaK<sub>6</sub>F][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>] and [KK<sub>6</sub>Cl][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>]: The Effect of Surface Area to Volume Ratios on Reaction
Products
Gregory Morrison
Hans-Conrad zur
Loye
10.1021/acs.cgd.5b01408.s001
https://acs.figshare.com/articles/journal_contribution/Flux_Growth_of_NaK_sub_6_sub_F_UO_sub_2_sub_sub_3_sub_Si_sub_2_sub_O_sub_7_sub_sub_2_sub_and_KK_sub_6_sub_Cl_UO_sub_2_sub_sub_3_sub_Si_sub_2_sub_O_sub_7_sub_sub_2_sub_The_Effect_of_Surface_Area_to_Volume_Ratios_on_Reaction_Products/2561794
Single crystals of
two new salt-inclusion uranium(VI) silicates,
[NaK<sub>6</sub>F][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>] and [KK<sub>6</sub>Cl][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>], were grown from
mixed alkali halide salt fluxes. Both compounds crystallize in the
[NaRb<sub>6</sub>F][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>] structure type in the orthorhombic space group <i>Pnnm</i> with lattice parameters <i>a</i> = 11.0819(5)
Å, <i>b</i> = 13.1149(6) Å, and <i>c</i> = 7.8418(4) Å ([NaK<sub>6</sub>F]) and <i>a</i> =
11.0830(7) Å, <i>b</i> = 13.5850(4) Å, and <i>c</i> = 7.8693(5) Å ([KK<sub>6</sub>Cl]). The surface area
to volume (sa/vol) ratio of the reaction, controlled by the reaction
vessel dimensions, has a strong influence on the reaction products
with small sa/vol ratios favoring the growth of the salt-inclusion
phases. Both compounds exhibit the typical luminescence of the uranyl
group with the luminescence of [KK<sub>6</sub>Cl][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>] being less intense
than [NaK<sub>6</sub>F][(UO<sub>2</sub>)<sub>3</sub>(Si<sub>2</sub>O<sub>7</sub>)<sub>2</sub>], likely due to quenching by the Cl<sup>–</sup> ions.
2016-02-02 00:00:00
reaction vessel dimensions
NaK 6F
compound
NaRb 6F structure type
KK 6Cl
ratio
alkali halide salt fluxes
Reaction ProductsSingle crystals
space group Pnnm
luminescence