Ai. Orlova et al., Synthesis and structure of complex orthophosphates of zirconium and alkalielements: 3. Isomorphism in Li-Zr, Na-Zr, and K-Zr phosphates, RADIOCHEMIS, 41(4), 1999, pp. 322-327
Orthophosphates of zirconium and alkali metals (Li, Na, K) were prepared an
d studied by IR spectroscopy and X-ray diffraction. Single-phase phosphates
with the structure similar to NaZr2(PO4)(3) (space group R (3) over bar c)
were found in the series of compounds with mutually different alkali eleme
nts A'(1-x)A(x)" Zr-2(PO4)(3) (0 less than or equal to x less than or equal
to 1) and A'(5-x)A(x)" Zr(PO4)(3) (0 less than or equal to x less than or
equal to 5), where A' and A " are Li, Na, and K, and the dependences of the
crystal structure of these phases on their chemical composition were evalu
ated. Simultaneous participation of lithium, sodium, and potassium in the s
tructure of phosphates, including substitution solid solutions, is due to o
ccupation of three types of nonequivalent crystallographic points by alkali
elements. Single-phase zirconium phosphate formulations with high concentr
ation of alkali elements in various ratios can be obtained.