xlrestraint computes the pathlength between attachment sites of a cross-linker to score structures. The accessible volumes of the cross-linker are computed as previously described. 1. Kalinin, S., T. Peulen, S. Sindbert, P. J. Rothwell, S. Berger, T. Restle, R. S. Goody, H. Gohlke and C. A. M. Seidel (2012). A toolkit and benchmark study for FRET-restrained high-precision structural modeling. Nature Methods 9(12) 1218-U1129.

2. Dimura, M., T. O. Peulen, C. A. Hanke, A. Prakash, H. Gohlke and C. A. M. Seidel (2016). Quantitative FRET studies and integrative modeling unravel the structure and dynamics of biomolecular systems." Current Opinion in Structural Biology 40 163-185.