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Quantum mechanical (QM) + molecular mechanics (MM) models are developed to represent potential energy surfaces (PESs) for the HBr(+) + CO2 → Br + HOCO(+) reaction with HBr(+) in the (2)Π3/2 and (2)Π1/2 spin-orbit states. The QM component is the spin-free PES and spin-orbit coupling for each state is represented by a MM-like analytic potential fit to spin-orbit electronic structure calculations. Coupled-cluster single double and perturbative triple excitation (CCSD(T)) calculations are performed to obtain "benchmark" reaction energies without spin-orbit coupling. With zero-point energies removed, the "experimental" reaction energy is 44 ± 5 meV for HBr(+)((2)Π3/2) + CO2 → Br((2)P3/2) + HOCO(+), while the CCSD(T) value with spin-orbit effects included is 87 meV. Electronic structure calculations were performed to determine properties of the BrHOCO(+) reaction intermediate and [HBr⋯OCO](+) van der Waals intermediate. The results of different electronic structure methods were compared with those obtained with CCSD(T), and UMP2/cc-pVTZ/PP was found to be a practical and accurate QM method to use in QM/MM direct dynamics simulations. The spin-orbit coupling calculations show that the spin-free QM PES gives a quite good representation of the shape of the PES originated by (2)Π3/2HBr(+). This is also the case for the reactant region of the PES for (2)Π1/2 HBr(+), but spin-orbit coupling effects are important for the exit-channel region of this PES. A MM model was developed to represent these effects, which were combined with the spin-free QM PES.

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Difficulties faced in life can affect marital relationships and such troubles may be dealt with in a multitude of ways, including coping religiously. The present study examined how religious coping, either in a positive or negative manner, may have an impact on marital satisfaction. Importantly, this association was studied dyadically in a sample of religiously diverse (Buddhists, 32.3%; Taoists, 17.6%; protestant Christians, 14.1%; and others who did not identify with a specific religion, 19.1%), married older Singaporean adults (N = 1928; 964 couples). Using actor-partner interdependence modeling, we found significant actor, partner, and combined actor-partner effects for positive and negative religious coping on marital satisfaction. Specifically, marital satisfaction was highest when both spouses reported high levels of positive religious coping and low levels of negative religious coping. Taken together, these findings suggest that it is the simultaneous act of either greater positive or lower negative religious coping by both spouses that is related to higher marital satisfaction.