
%0 Journal Article
%A Semenova, Lioubov I. 
%A White, Allan H. 
%T Structural Systematics of Rare Earth Complexes. XVII Hydrated 1 : 1 Adducts of 2,2&#8242;:6&#8242;,2&Prime;-Terpyridine with the Lanthanoid(<emph type="6">III</emph>) Bromides and Some Binuclear Hydroxy-Bridged Dimers
%J Australian Journal of Chemistry
%D 1999/08/05
%V 52
%N 6
%P 539-550
%K 
%R https://doi.org/10.1071/CH98048
%U https://www.publish.csiro.au/paper/CH98048 
%X Room-temperature single-crystal X-ray structural characterizations are recorded for hydrated lan- thanoid(III) bromide/2,2&#8242;:6&#8242;,2&Prime;-terpyridine (tpy) (1 : 1) complexes, showing all to be ionic and of the form &#91;(tpy)Ln(OH2)x&#93;Br3.yH2O, where x and y are 6 and 1 for the isomorphous series Ln = La(-)Er (and intermediate members, by presumption), and 5 and various values for Ln = Tm, Yb, Lu. Crystals of &#91;(tpy)Ln(OH2)6&#93;Br3.H2O are monoclinic, P 21/c, a &#x2248; 8&#183;5, b &#x2248; 18, c &#x2248; 16&#183;3 &#197;, &#946; &#x2248; 108&#176;, Z = 4; for Ln = La, Er, conventional R values on &#124;F&#124; were 0&#183;048, 0&#183;080 for No 4027, 1347 &#8216;observed&#8217; (I &#62; 3&#963;(I)) diffractometer reflections respectively. The complex &#91;(tpy)Tm(OH2)5&#93;Br3.H2O is monoclinic, P 21/c, a 8&#183;506(4), b 17&#183;376(1), c 15&#183;951(6) &#197;, &#946; 106&#183;87(3)&#176;, Z = 4, (quasi-)isomorphous with the Ln = La-Er array, R 0&#183;065 for No 2067. &#91;(tpy)Yb(OH2)5&#93;Br3.4H2O is triclinic, P 1, a 11&#183;902(2), b 11&#183;639(3), c 9&#183;831(2) &#197;, &#945; 98&#183;92(2), &#946; 106&#183;84(2), &#947; 92&#183;42(2)&#176;, Z = 2, R 0&#183;062 for No 3422, while &#91;(tpy)Lu(OH2)5&#93;Br3.H2O is monoclinic, P 21/n, a 13&#183;635(8), b 9&#183;022(5), c 19&#183;03(1) &#197;, &#946; 99&#183;02(5)&#176;, Z = 4, R 0&#183;043 for No 3139. Despite a common N3LnO5 coordination sphere in the last three compounds, subtle differences are found in stereochemistry; in the N3LnO6 array, one of the outer water molecules becomes progressively detached as the lanthanoid radius contracts. Some tendency is found toward the end of the lanthanoid series toward the formation of di(hydroxy-bridged) neutral dimers, Ln(OH)Br2/tpy/H2O(1 : 1 : 8)(&#215;2), &#91;(tpy)(H2O)3Ln(&#181;-OH)2Ln(OH2)3(tpy)&#93;Br4.10H2O, monoclinic, C 2/c, a &#x2248; 19&#183;5, b &#x2248; 14&#183;5, c &#x2248; 17&#183;1 &#197;, &#946; &#x2248; 92&#176;, Z = 4 dimers, thus far defined by full determinations for the extrema Lu = Er, Lu (and Y), R 0&#183;055, 0&#183;043, (0&#183;047) for No 3141, 4591, (2991) respectively; the dimer is disposed about a crystallographic 2 -axis. An Ln = Dy example, seemingly isomorphous, has also been characterized by cell determination. 
