Hopping dynamics

Ishizaki A, Fleming GR (2009) Unified treatment of quantum coherent and incoherent hopping dynamics in electronic energy transfer reduced hierarchy equation approach. J Chem Phys 130 234111... 

D. Mac Kernan, G. Ciccotti, and R. Kapral. Surface-hopping dynamics of a spin-boson system. J. Chem. Phys., 116(6) 2346-2353, 2002. 

Nielsen, S., Kapral, R., Ciccotti, G. Mixed quantum-classical surface hopping dynamics. J. Chem. Phys. 112 6543 (2000). 

The universality of the relaxation time near the crossover temperature also originates in the dynamic nature of supercooled liquids. The idea here is that supercooled liquids have collective excitations. These elementary excitations have characteristics of phonons [119-122]. Furthermore, there is a unique temperature at which the lifetime for the elementary excitation becomes comparable to the lifetime of hopping dynamics on the potential energy surface [119]. Analysis indicates that the value of crossover relaxation time at this characteristic temperature is < ) x 10-7 5 s, where < ) varies between 1 and [ 119]. 

If each single hopping step occurs over the same distance, then the hopping dynamics will display a weak distance dependence, varying inversely with respect to a small power of the number, N, of hopping steps, viz. Eq. 25 [125-127] ... 

By dealing with the evolution of constraints (i.e., Ramachandran basins) rather than the backbone torsional coordinates themselves, the dynamics are judiciously simplified [31]. The algorithm consists of a stochastic simulation of the coarsely resolved dynamics, simplified to the level of time-evolving Ramachandran basin assignments. An operational premise is that steric restrictions imposed by the side chains on the backbone may be subsumed into the basin-hopping dynamics. The side chain constraints define regions in the Ramachandran map that can be explored in order to obtain an optimized pattern of nonbonded interactions. 

D. McKernan, R. Kapral, and G. Ciccotti (2002) Surface-Hopping Dynamics of a Spin-Boson System. J. Chem. Phys. 116, pp. 2346-2353... 

Zhang, Z., Metiu, H. Adsorbate migration on a solid surface The connection between hopping dynamics and the atom-surface interaction energy, J. Chem. Phys. 1990, 93, 2087. 

Maass P, Rinn B, Schirmacher W (1999) Hopping dynamics in random energy landscapes an effective medium approach. Philos Mag B 79 1915-1922... 

Kuntz PJ (1991) Qassical path surface-hopping dynamics. 1. General-theory and illustrative trajectories. J Chem Phys 95 141... 

Recently, Funke and co-workers [56] explored the concept of ion hopping dynamics in disordered materials. Following their approach, stmctural and dynamic disorders are the key factors to understand ion conduction in FIC glasses. Here, ionic transport can no longer be described in terms of individual defects performing random walks in a static energy landscape, but rather in terms of a more challenging many-particle problem, with the mobile ions... 

Surface hopping dynamics simulations of PSB3 with the semiempirical OM2 method (Keal et al. 2009) show a picture very distinct from the CASSCF simulations. Depending on the choice of active space, the excited state relaxation shows a bi-exponential decay profile of the Si population, with a fast sub-picosecond time constant and a picosecond time constant. Overall, the relaxation process is predicted to be larger than 600 fs, much slower than the 100 fs predicted by CASSCF. Similar multi-exponential decay has also been described in wave packet propagation on a two-dimensional surface model for RPSB (Santoro et al. 2007b). 

Antol, I., Eckert-Maksid, M., Barbatti, M., Lis-chka, H. (2007). Simulation of the photodeactivation of formamide in the noTt and 7t7t states An ab initio on-the-fly surface-hopping dynamics study. Journal of Chemical Physics, 127(23), 234303-234308. doi 10.1063/1.2804862. 

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