Pathway tubes interference effects

Effects of nuclear dynamics on electron tunneling in redox proteins have been an important question for the biological electron transfer community. While it has been understood how nuclear dynamics controls the Pranck-Condon factor, little was known until now about how the dynamics affects the tunneling matrix element. Our results show that, when tunneling is dominated by a single pathway tube, dynamical effects are small and Pathways level calculations provide reasonable results. The situation changes when several pathway tub are important and destructive interference exists among them. In this case dynamic amplification becomes important,... 

The first step in the tube approach is to use the pathways idea to isolate routes through the protein that are physically distinct (see the example in the next section), and then use these paths as tube cores. The analysis then proceeds with an emphasis on partitioning the protein into tubes the tubes contain trivial interference effects, but they can expose crucial interference between tubes. This is something which one cannot do in the single-pathway approximation. 

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