The role of steric factor of a substituent in deformation of equatorial plane of uranyl six-coordination compounds

The effect of increase in the equatorial plane perimeter of uranium atom coordination polyhedron with an increase in substituent volume (steric effect) has been demonstrated, using uranyl oxalate complexes with hydroxylamine and its derivatives by way of example. A correlation of the complexes polymerization degree (monomer, dimer, polymer) in crystal state and changes in coordination polyhedron equatorial plane perimeter is pointed out. The nature of the effect is discussed, making allowance of the character of M-O bonds. 10 refs.; 2 figs