TY - JOUR
T1 - Structural systematics of rare earth complexes. XXII ('Maximally') hydrated rare earth iodides
AU - Lim, K.C.
AU - Skelton, Brian
AU - White, Allan
PY - 2000
Y1 - 2000
N2 - Low-temperature (c. 153 K) single-crystal X-ray structure determinations, carried out on trivalent rare earth iodides crystallized from aqueous solution at room temperature, have defined two series of hydrates, LnI(3 .)nH(2)O. For Ln = La-Ho, a nonahydrate phase (n = 9) is defined, orthorhombic Pmmn, a similar to 11.5, b similar to 8.0, Angstrom similar to 8.8 Angstrom, Z = 2, the second phase (n = 10), monoclinic P2(1)/c, Z = 4 being defined for Ln = Er-Lu, a similar to 8.2, b similar to 12.8, c similar to 17.1 Angstrom, beta similar to 103.7 degrees. Neither of these phases is isomorphous with any of those pertinent to the previously studied chloride or bromide (hydrated) arrays, nor, unlike those, does the halide (iodide) in any case enter the coordination sphere of the lanthanoid. The n = 9 phase takes the form [Ln(OH2)(9)]I-3, the nine-coordinate lanthanoid environment stereochemistry being tricapped trigonal-prismatic, while the n = 10 phase is [Ln(OH2)(8)]I(3 .)2H(2)O, the eight-coordinate lanthanoid environment being square-antiprismatic.
AB - Low-temperature (c. 153 K) single-crystal X-ray structure determinations, carried out on trivalent rare earth iodides crystallized from aqueous solution at room temperature, have defined two series of hydrates, LnI(3 .)nH(2)O. For Ln = La-Ho, a nonahydrate phase (n = 9) is defined, orthorhombic Pmmn, a similar to 11.5, b similar to 8.0, Angstrom similar to 8.8 Angstrom, Z = 2, the second phase (n = 10), monoclinic P2(1)/c, Z = 4 being defined for Ln = Er-Lu, a similar to 8.2, b similar to 12.8, c similar to 17.1 Angstrom, beta similar to 103.7 degrees. Neither of these phases is isomorphous with any of those pertinent to the previously studied chloride or bromide (hydrated) arrays, nor, unlike those, does the halide (iodide) in any case enter the coordination sphere of the lanthanoid. The n = 9 phase takes the form [Ln(OH2)(9)]I-3, the nine-coordinate lanthanoid environment stereochemistry being tricapped trigonal-prismatic, while the n = 10 phase is [Ln(OH2)(8)]I(3 .)2H(2)O, the eight-coordinate lanthanoid environment being square-antiprismatic.
U2 - 10.1071/CH00119
DO - 10.1071/CH00119
M3 - Article
VL - 53
SP - 867
EP - 873
JO - Australian Journal of Chemistry:an international journal for chemical science
JF - Australian Journal of Chemistry:an international journal for chemical science
SN - 0004-9425
IS - N/A
ER -