Structural Investigation of Bond-Isomeric Hexakis (Thiocyanato-isothiocyanato) osmates (III) from Os Lm-Edge EXAFS

T h e e x t e n d e d x r a y absorption fine-structure ( E N A F S ) has been used t o determine b o n d lengths a n d coordination n u m b e r s around the central O s a t o m in b o n d i s o m e r i c hexakis (thioc y a n a t o i s o t h i o c y a n a t o ) o s m a t e s ( I I I ) [ O s ( N C S ) n ( S C N ) 6 w ] 3 ~ , n — 1 , . . . , 6 : T h e a b o v e assignm e n t o f the species with w-values is confirmed. T h e O s N b o n d length decreases with increasing n while the O s S b o n d length is the same in all c o m p o u n d s . T h e N b o n d e d l igands f o r m a n u n distorted linear chain with the central O s a t o m . T h e b o n d angles b e t w e e n t h e S b o n d e d l igands a n d O s a t o m s are distorted b y at least 10° around their a v e r a g e va lue ( ~ 1 0 5 ° ) .