Interaction of lysine with iodic acid.

A new compound in the Lys-HIO(3)-H(2)O system (where Lys = lysine), lysine-iodic acid (1/3), C(6)H(14)N(2)O(2).3HIO(3), has been discovered. Its crystals display nonlinear optical properties. They were investigated by X-ray analysis, IR spectroscopy and NQR methods. The parameters of the unit cell are a = 8.360 (2), b = 6.330 (1), c = 14.750 (3) Å, beta = 92.86 (3) degrees, D(x) = 2.87 Mg m(-3), space group P2(1), Z = 2. The three iodate groups in the structure have different roles. Interaction of lysine and iodic acid results in a compound containing a doubly protonated lysine cation and two counterions, IO(3)(-) and I(2)O(5)OH(-).