The theoretical study on interaction of hydrogen with single-walled boron nitride nanotubes. I. The reactive force field ReaxFF(HBN) development.

We present a new reactive force field ReaxFF(HBN) derived to accurately model large molecular and condensed phase systems of H, B, and N atoms. ReaxFF(HBN) has been tested against quantum calculation data for B-H, B-B, and B-N bond dissociations and for H-B-H, B-N-B, and N-B-N bond angle strain energies of various molecular clusters. The accuracy of the developed ReaxFF(HBN) for B-N-H systems is also tested for (i) H-B and H-B bond energies as a function of out of plane in H-B(NH2)3 and H-N(BH2)3, respectively, (ii) the reaction energy for the B3N3H6+H2-->B3N3H8, and (iii) crystal properties such as lattice parameters and equations of states for the hexagonal type (h-BN) with a graphite structure and for the cubic type (c-BN) with a zinc-blende structure. For all these systems, ReaxFF(HBN) gives reliable results consistent with those from quantum calculations as it describes well bond breaking and formation in chemical processes and physical properties. Consequently, the molecular-dynamics simulation based on ReaxFF(HBN) is expected to give a good description of large systems (>2000 atoms even on the one-CPU machine) with hydrogen, boron, and nitrogen atoms.