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A general equation for the three-dimensional angular distribution of photoelectrons ejected from fixed-in-space molecules of any symmetry by light of arbitrary polarization is derived. The state of the light polarization is described by the Stokes parameters. The equation is also valid for photoionization of polarized atoms and aligned or oriented rotating molecules. In the particular case of linear molecules the three-dimensional angular distribution of photoelectrons is fully characterized by five two-dimensional angular distributions. Simple ways to determine experimentally these two-dimensional functions are mentioned. The application of general equations is illustrated by a numerical example of photoionization of the C K-shell of CO molecule in the region of the σ∗ shape resonance.

We present the full quantum mechanical expressions for the polarization differential cross sections of the photofragments produced in slow predissociation of a parent molecule via isolated rotational branches. Both radial and Coriolis nonadiabatic interactions between the molecular potential energy surfaces have been taken into account. The expressions describe the recoil angle distribution of the photofragments and the distributions of the photofragment angular momentum polarization (orientation and alignment) in terms of the anisotropy parameters of the ranks K=0,1,2. The explicit expressions for the anisotropy parameters are presented and analyzed which contain contributions from different possible photolysis mechanisms including incoherent, or coherent optical excitation of the parent molecule followed by the radial, or Coriolis nonadiabatic transitions to the dissociative states. The obtained expression for the zeroth-rank anisotropy parameter beta is valid for any molecule and for an arbitrary value of the molecular total angular momentum J. The expressions for the orientation (K=1) and alignment (K=2) anisotropy parameters are given in the high-J limit in terms of the generalized dynamical functions which were analyzed for the case of photolysis of linear/diatomic molecules. As shown, the Coriolis nonadiabatic interaction results in several new photolysis mechanisms which can play an important role in the predissociation dynamics.

We present the quantum mechanical expressions for the angular momentum distribution of the photofragments produced in slow predissociation. The paper is based on our recent theoretical treatment [J. Chem. Phys. 123, 034307 (2005)] of the recoil angle dependence of the photofragment multipole moments which explicitly treat the role of molecular axis rotation on the electronic angular momentum polarization of the fragments. The electronic wave function of the molecule was used in the adiabatic body frame representation. The rigorous expressions for the fragment state multipoles which have been explicitly derived from the scattering wave function formalism have been used for the case of slow predissociation where a molecule lives in the excited quasibound state much longer than a rotation period. Possible radial nonadiabatic interactions were taken into consideration. The optical excitation of a single rotational branch and the broadband incoherent excitation of all possible rotational branches have been analyzed in detail. The angular momentum polarization of the photofragments has been treated in the high-J limit. The polarization of the photofragment angular momenta predicted by the theory depends on photodissociation mechanism and can in many cases be significant.

We present the quantum-mechanical expressions for the recoil angle dependence of the photofragment multipole moments which explicitly treat the role of molecular axis rotation on the electronic angular momentum polarization of the fragments. The paper generalizes the result of Siebbeles et al. [J. Chem. Phys. 100, 3610 (1994)] to the case of dissociation of rotating molecules. The electronic wave function of the molecule was used in the adiabatic body-frame representation. The obtained rigorous expressions for the fragment state multipoles have been explicitly derived from the scattering wave-function formalism and then simplified using the quasiclassical approximation in the high-J limit. Possible radial and Coriolis nonadiabatic interactions have been taken into consideration. It is shown that the rotation of the molecular axis is described by a number of rotation factors which depend on the rank of the incident-photon polarization matrix, on the dissociation mechanism, and on the classical angle of rotation of the molecular axis gamma.