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In contradiction to the prediction of the Periodic Table but in agreement with earlier suggestions by Brewer and Mann, the ground state configuration of atomic Lawrencium (Z = 103) will not be 7s2 6d 2D 3/2 but 7s2 7p 2P1/2. The reason for this deviation from normal trends across the Periodic Table are strong relativistic effects on the outermost 7p1/2 orbital. Multiconfiguration Dirac-Fock calculations are reported for Lawrencium and analogous lighter atoms. These calculations include contributions from magnetic and retardation interactions and an estimation of quantum electrodynamic corrections

CONCLUSIONS NMR studies can yield information on the dynamics of domain walls in materials where the signals arise from nuclei within domain walls. 'In addition, it has been shown that an NMR study can be used to study the static arrangement of spins within a domain wall somewhat quantitatively.In particular, it has been found that the strongly pinned domains in hematite having approximately 180' AF walls (which are difficult to remove with an applied field) are responsible for the largest contribution to the positive-phase NMR signal.The experimental data also suggest that the anomalous temperature dependence of M(T) may be related to these strongly pinned walls. It is suggested that careful magnetization measurements in extremely large fields might clear up this point.

Results of the DiracSlater discrete variational calculations for the group 4,5, and 6 highest chlorides including elements 104, 105, and 106 have shown that the groups are not identical with respect to trends in the electronic structure and bonding. The charge density distribution data show that notwithstanding the basic increase in covalency within the groups this increase diminishes in going from group 4 to group 6. As a result, E106C16 will be less stable toward thermal decomposition than W C L which is confirmed by an estimated low E 1 0 6 4 1 bond energy. AHform equal to -90.3 f 6 kcal/mol is obtained for ElO6Cl6 in the gas phase, which is indicative of a very low stability of this compound. The stability of the maximum oxidation state is shown to decrease in the direction E104(+4) > E105(+5) > E106(+6).