Metals 1 Quantum Mechanics f Spectroscopy, Nuclear Magnetic Resonance f Wave FunctionsFor Li and Na metals we investigated theoretically the pressure dependence of the atomic spin susceptibility xA, the probability density PF and the Knight shift K, = (8x/3)xAPF by the spin polarized version of the scalar relativistic augmented plane wave method. The calculations were performed within the volume range V, 2 V 2 0.5 Vo, where Vo is the volume at 1 bar. Recently it was found experimentally by Bertani et al. that a) the slopes of the curves K, = Ks( V ) have different signs for lithium and sodium metals and b) for high pressures K,(V) goes through a minimum for Na metal. We found in the present investigation that this behavior can be understood in terms of a competition between the pressure dependence of xA and PF for these metals.

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Summary: Catalyst systems for polymerization often exhibit variable and poorly controllable activity because of strong influences of trace components and catalyst preparation conditions. In cationic polymerizations in particular, determining catalytic activity and hence the amount of catalyst to be used is challenging. The assessment of a given initiator system typically requires testing it in polymerization reactions. Determining catalytic activity before using the initiator in a polymerization reaction is a desirable approach. This contribution describes the development of such an activity monitoring tool. In the first part, results from a fundamental characterization of the system diethylaluminum chloride/ethylaluminum dichloride/water by different NMR measurements and elemental analysis are reported. Structures characteristic of catalytically active systems are presented. The second part describes the application of transmission IR to the characterization of this system and the correlation of IR results to catalytic activity in dimerization and polymerization reactions. Implementation of the IR analysis as an on‐line measurement is demonstrated.

The electrostatic crystal potentials V(r) of the cubic metals Pd, V, Nb, Ta, and the intermetallic phases FeTi and XEr, X = Cu, Ag, Au, have been determined by the full potential augmented‐plane‐wave method (FP‐APW). Furthermore, to study the electronic states in dilute metal‐hydrogen‐systems the partial densities of states have been calculated by the supercell procedure using the augmented‐spherical‐wave method (ASW) for PdH1/32. The results are compared with the values for PdH1/4, PdH, and Pd. – A relation is found between the depth of the host lattice electrostatic potential and the occupation of interstitial lattice sites by hydrogen in the metal‐hydrogen α‐phases. For bcc V, Nb, and Ta the crystal potential “seen” by a proton has its deepest minimum at the tetrahedral site, for fcc Pd the minimum occurs at the octahedral site and in FeTi (B2‐type) the minimum of Vproton(r) is found for the octahedral site surrounded by 2 Fe atoms and 4 Ti atoms. In all these cases the calculated site of the minimum is in accordance with the location of hydrogen in the respective α‐phases found experimentally by neutron scattering. For XEr. X = Cu, Ag, Au, a preferred occupation by hydrogen is predicted.

The electric field gradient (EFG) in body-centered tetragonal Indium metal and hexagonal closed packed Beryllium metal is calculated on the basis of a full potential scalar relativistic augmented plane wave procedure. The various contributions to the EFG in simple metals are discussed. The total EFG in In metal found theoretically is equal to q