Atomic transition rates and f values have been calculated in the triplet and quintet systems and for some intercombination lines of neutral oxygen. Configuration interaction was included in the calculations performed with the CIV3 code of Hibbert (1975) for all the transitions connecting the n=3 and n=4 energy levels. In order to reproduce the observed energy splittings between the energy states, small empirical adjustments were introduced to the diagonal matrix elements. Comparisons with previously published f values and radiative lifetimes are discussed and the subsequent astrophysical applications of the results are briefly mentioned.

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Using the quantum chemistry package MOLPRO and an adapted basis set, we have calculated the adiabatic potential energy curves of the first 20 1 + , 19 3 + , 12 1 , 9 3 , 4 1 and 2 3 electronic states of the HeH + molecular ion in CASSCF and CI approaches. The results are compared with previous works. The radial and rotational non-adiabatic coupling matrix elements as well as the dipole moments are also calculated. The asymptotic behaviour of the potential energy curves and of the various couplings between the states is also studied. Using the radial couplings, the diabatic representation is defined and we present an example of our diabatization procedure on the 1 + states.

The total and partial photodissociation cross sections of the molecular ion HeH + are computed by timedependent methods for fragmentation into the excited shells n =1,2,3 up to a photon energy of 40 eV. 1 ⌺ + and 1 ⌸ states are considered for parallel and perpendicular transitions for different initial rotational or vibrational excitations. Nonadiabatic radial and rotational couplings are taken into account. The results from coupledchannel equations are compared with the Born-Oppenheimer approximation. A time-dependent calculation with a femtosecond laser pulse is carried out to simulate a recent crossed beam photodissociation imaging experiment with vacuum ultraviolet free-electron laser ͓H. B. Pedersen et al., Phys. Rev. Lett. 98, 223202 ͑2007͔͒. The dominance of photodissociation perpendicular to the photon polarization is confirmed.

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We report extensive multiconfiguration Hartree-Fock (MCHF) calculations, taking into account valence correlation and core-relaxation effects, of energy levels, eigenvector compositions, electric dipole and quadrupole oscillator strengthsstates in Ca 1. On the whole, the agreement between theory and obselvation has been improved by our set of MCHF results. The theoretical transition probabilities allow the evaluation of the lifetimes for the levels 454p, 4s5p 'Po; 4s4d,4p2 'D and 3d4p, 4s4f 'Fo which are compared with the most recent measurements. The differences between MCHF calculations for series perturbed by doubly-exdted states in Ca and Sr are discussed. It is concluded that corepolarization effects are of about the same importance in the two atom but that the effects on the 3d (Ca) and 4d (Sr) orbitals are such that the total core-polarization effects for series and perturbers are of the same magnitude in Sr while large differences exist in Ca.

Calculations are presented of energy level values, radiative transition probabilities and autoionisation rates for terms belonging to the ls23/31' configurations for several ions in the Be I isoelectronic sequence (C2+, N3+, 04+, Ne6+ and Xe5"+). The results of a C I calculation including the configurations of the complex (and the 3d4f configuration) are compared with experimental results obtained in collisions of highly stripped ions with He, H 2 and Ar and with the results of theoretical calculations.