[1
]Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202,
USA
[2
]Laboratoire de Biochimie Théorique, UPR 9080, CNRS, Université Denis Diderot, Sorbonne
Paris Cité, IBPC, 13 rue Pierre et Marie Curie, 75005 Paris, France