The deposition 3fiy from the start of last year might be of interest: FORMUL 2 NA 199(NA 1+) FORMUL 20 HOH *256(H2 O)
It is annoying that the periodic table offers such a discrete range of sizes for 1+ ions; I hoped the lanthanide contraction would provide a heavy sodium substitute with lots of anomalous scattering, but (if I believe http://en.wikipedia.org/wiki/Ionic_radius) no ... Ag+ is the closest match in size (still 15% or so bigger) but silver(I) compounds are usually insoluble, La3+ is the same size as Na+, and LaCl3 nicely soluble, but obviously it coordinates very differently. Tom
