An accelerated quantum chemical molecular dynamical code "Colors-Excite'' was used to investigate the photolysis of alkyl nitrites series, RONO (R=CH3 and C(CH3)(3)) on copper surfaces. Our calculations showed that the photo-dissociated processes are associated with the alkyl substituents of RONO when adsorbed on copper surfaces. For R=CH3, a two-step photolysis reaction occurred, yielding diverse intermediate products including RO radical, NO, and HNO, consistent with those reported in gas phase. While for R=C(CH3)(3), only one-step photolysis reaction occurred and gave intermediate products of RO radical and NO. Consequently, pure RO species were achieved to adsorb on metal surfaces by removing the NO species in photolysis reaction. The detailed photo-dissociated behaviors of RONO on copper surfaces with different alkyl substituents which are uncovered by the present simulation can be extended to explain the diverse dissociative mechanism experimentally observed. The quantum chemical molecular dynamical code "Colors-Excite'' is proved to be highly applicable to the photo-dissociations on metal surfaces. (C) 2008 Elsevier B. V. All rights reserved.