Papers Published

  1. D. Tang and P. Attar and A. Q. Li and E. H. Dowell, Complex dynamics of a pyranose ring structure molecule attached to an atomic force microscope, Nonlinear Dynamics, vol. 45 no. 3-4 (August, 2006), pp. 283 -- 303 .
    (last updated on 2009/08/04)

    Dynamic numerical simulations were performed for a pyranose ring structure molecule attached to an Atomic Force Microscope (AFM) using a standard semiempirical potential energy surface model. The fundamental static force-extension behavior was first determined using a slow pulling base excitation at the AFM probe. The static force-extension curve displays a stiffness nonlinearity, both softening and hardening, that depends upon level of the pulling force. For the dynamic analysis, a single harmonic base excitation is applied to the AFM probe. A typical evolution process from periodic to aperiodic or chaotic motion obtained by varying the excitation frequency and amplitude is discussed. A strong chaotic response motion was generated for certain system parameters. The numerical analysis shows this chaotic response arises from a molecular structure conformational change.