Secondader vibmnic reduction factors are derived for strongly coupled orbital triplet systemscoupled to t2 modesofvibration usingthe recently derived symmetry-related method. This involves the calculation of oscillator overlaps which are projected out of cubic vibronic states. Details are presented for examples where the perturbations are both of Etype symmetry, where they are both of T,type symmetry and where they are of mixed E-andT,typesymmetries. Thesymmetrypropertiesofthe resultsarediscussedandcompared with those obtained previously for perturbations of T, symmetry, such as those for spinorbit coupling. The new calculations me appropriate when a description of second-order uniaxial stresses for strongly coupled systems is requiredsuch as in the study of deep-level impurities in semiconductors.

Analytical expressions for both first- and second-order reduction factors are obtained for orbital doublet systems which are strongly coupled to their surroundings using a recently derived transformation method. The problem is often referred to as the E (X) e Jahn-Teller system. The reduction factors are found from the symmetry-adapted cubic vibronic states, which have been derived in the preceding paper, in the presence of some warping in the potential energy trough. The results for the first-order reduction factors are shown to compare favourably with earlier numerical results, although the configurations are necessarily different. The calculations of the second-order reduction factors appear to be the first of their type for this system. It is shown how they may be used in modelling experimental data involving orbital doublets for E-type uniaxial stresses.

Projection operator techniques are used to construct a complete set of symmetry-adapted excited states for the strongly coupled E (X) e Jahn-Teller (JT) system from the exact infinite coupling states in the presence of warping described by a quadratic coupling term. All possible phonon excitations are considered. The associated ion is assumed to occupy a site of tetrahedral Td symmetry such as that occurring at substitutional sites in III-V semiconductors. The purpose of the calculation is to obtain an appropriate set of basis states from which first- and, more particularly, second-order JT reduction factors can be calculated by analytical methods as described in the companion paper. The states are used in this paper to obtain the energy level diagram for the first few excited states for a chosen value of the warping parameter L.

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Activation energies determined from Arrhenius plot for cobalt-boron liquid quenched amorphous alloys in the temperature range 40 K < T < 300 K , suggest vacancy and interstitial formation to nucleate crystalline phases in an amorphous matrix preferably at sites where dangling bonds are present. Nucleation of crystallites with preferential tetragonal or orthorhombic structures is a self-evolving process due to catalytic presence of dangling bonds in an amorphous material and that the occurrence of negative activation energies support this evidence.