Forcefield_NCAA is a set of self-consistent AMBER forcefield parameters for non-canonical amino acids. It allows you to design and derivatize peptides containing NCAAs for use as drugs.
AMBER (Assisted Model Building with Energy Refinement) refers to two things: a set of molecular mechanical force fields for the simulation of biomolecules (which are in the public domain, and are used in a variety of simulation programs); and a package of molecular simulation programs which includes source code and demos.
D.A. Case, T.E. Cheatham, III, T. Darden, H. Gohlke, R. Luo, K.M. Merz, Jr., A. Onufriev, C. Simmerling, B. Wang and R. Woods. The Amber biomolecular simulation programs. J. Computat. Chem.26, 1668-1688 (2005).
AmberTools consists of several independently developed packages that work well by themselves, and with Amber (Assisted Model Building with Energy Refinement) itself. The suite can also be used to carry out complete (non-periodic) molecular dynamics simulations (using NAB), with generalized Born solvent models.
AmberTools consists of 7 main codes
NAB build molecules; run MD or distance geometry, using generalized Born, Poisson-Boltzmann or 3D-RISM implicit solvent models
antechamber Create force fields for general organic molecules
ptraj Analyze trajectories from Amber or CHARMM
tleap and xleap Basic preparation program for Amber simulations
sleap replaces and expands tleap
sqm semiempirical and DFTB quantum chemistry program
pbsa Performs numerical solutions to Poisson-Boltzmann models
D.A. Case, T.E. Cheatham, III, T. Darden, H. Gohlke, R. Luo, K.M. Merz, Jr., A. Onufriev, C. Simmerling, B. Wang and R. Woods. The Amber biomolecular simulation programs. J. Computat. Chem.26, 1668-1688 (2005).