Polyhydride seven-coordinate

X-ray structural data also exist for two seven-coordinate polyhydrides, H3Re(DPPE)(PPh3)2 and H3Re(DPPE)2 (30) (DPPE is bisdiphenylphosphi-noethane, also known as diphos). Analysis of the data for the latter compound... 

After the advent of the nonclassical if-Vi.2 complexes, polyhydrides had to be reinterpreted [14]. Thus, RuH4(PPh3)3 is not a classical tetrahydride of coordination number seven at the ruthenium atom but a dihydride-dihydrogen complex Ru(H2)(H)2(PPh3)3 of octahedral geometry [25]. 

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