Interlayer hopping

On the other hand, the rope of SWCNTs gave an increase of resistivity with increasing temperature which suggests the existence of metallic CNTs [21], This is accounted for by the small effect of inter-chain barrier and the absence of interlayer hopping processes. 

The first interesting question is whether the interlayer hopping occurs directly across the Y layer (the hopping distance is small, but lack of the bridging oxygen in the Y layers hinders hopping) or via a longer path Cu2-04—Cul-04-Cu2, where each step is easier... 

In the smectic phase of scLCPs, interactions between the liquid-crystalline and the backbone chain moieties takes a much more dramatic form. The side chains form the strongly interacting part of the smectic layers, while the weakly interacting backbone chain completes the layer and is basically excluded from the strongly interacting part. In a well-developed smectic phase the main chain thus finds itself very nearly confined to a two-dimensional plane within the smectic layers, with occasional interlayer hopping (see Fig. 4.13(c)). 

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