Identification of complexes of Nd(III) with dithiophosphinic acids verifying the difference in complexation between Ln(III) and An(III).

Five complex species of Nd(III) with HA have been spectroscopically and compositionally identified as NdA 3 , NdA 3 (HA), NdA 3 (HA)H 2 O, NdA 3 (H 2 O) 3 , and Nd(H 2 O) 23 ·3A (HA, bis(2,4,4-trimethylpentyl)dithiophosphinic acid) with the help of X-ray diffraction analysis on single crystals of Nd(H 2 O) 9 ·H 2 O·3B (HB = bis(iso-butyl)dithiophosphinic acid.