A 6-coordinate complex may be obtained by crystallizing anhydrous CaI2 from THF solution at 253k. In contrast when BaI2 crystalizes from THF at 253k,...

A 6-coordinate complex may be obtained by crystallizing anhydrous CaI2 from THF solution at 253k. In contrast when BaI2 crystalizes from THF at 253k, a 7-coordinate complex is obtained. Suggest structures for the two complexes, and comment on possible isomerism and factors that may favour one particular isomer in each case. Rationalize why CaI2 and BaI2 form complexes with THF that have different coordination numbers.

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