(8) The conventional reliability index R= Zwl kl Fol-I F, II/Zwl F,, is cited throughout. Scattering factors for carbon and oxygen are taken from D. Cromer and J. Waber, Acta Crystallogr., 18, 104 (1965), while that for hydrogen is taken from R. Stewart, E. Davidson, and W. Simpson, J. Chem. Phys., 42, 3175 (1965).
