Floppy Tethered Networks

A model for extremely flexible tethered membranes is studied by Monte Carlo simulations and scaling arguments. In contrast to the standard string-and-bead models, no finite-range hard-core repulsion is used to ensure self-avoidance. Instead, the elementary triangles are taken to be impenetrable. Although this leads to an extremely floppy tethered network, the surface is found to be asymptotically flat, with a roughness exponent ( cf 0.7, consistent with the result of self-avoiding string-and-bead models. The orientationally averaged scattering intensity, on the other hand, is found to exhibit a nontrivial scaling behavior characteristic of a crumpled object with an effective fractal dimension df cf 2.7. This result is compared with recent experiments on graphite oxide sheets.