title: Effect of van der Waals interaction on the geometric and electronic properties of DNA nucleosides adsorbed on Cu(111) surface: a DFT study.
abstract: The geometrical properties and electronic structure of DNA nucleosides (deoxyadenosine, thymidine, deoxyguanosine, deoxycytidine) adsorbed on a metallic surface of Cu(111) are determined using density functional theory computations. In order to assess the effect of the long-range interaction upon the results of the DFT simulations, we compare the results of a standard GGA exchange-correlation functional with those produced by the newly developed van der Waals exchange-correlation functional. The most striking difference between the two sets of results occurs for the adsorption energies: standard functional predicts values representing about 30% of those obtained when van der Waals interaction is taken into account. The standard GGA functional favors slightly tilted orientation of the DNA bases with respect to the surface, while the inclusion of the van der Waals effect leads to an almost parallel orientation of the bases with the surface. On the other hand, the position of the sugar pucker is less influenced by the type of the exchange-correlation used. According to our studies, in the presence of long-range interactions, the molecule-surface charge transfer is qualitatively affected. Standard functional predicts a decrease of the electronic population of the adsorbate, while the presence of long-range interaction leads to an opposite effect.
authors: National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath Street, 400293 Cluj-Napoca, Romania.
authors: Diana
authors: D
authors: Bogdan
authors: Cristian
authors: C
authors: Morari
mesh_terms: D000327:Adsorption; D003300:Copper / Q000737:chemistry*; D003839:Deoxyadenosines / Q000737:chemistry*; D003841:Deoxycytidine / Q000737:chemistry*; D003849:Deoxyguanosine / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D011789:Quantum Theory; D013499:Surface Properties; D013816:Thermodynamics; D013936:Thymidine / Q000737:chemistry*; D014867:Water
chemical_list: D003839:Deoxyadenosines; D014867:Water; D003841:Deoxycytidine; D003300:Copper; D003849:Deoxyguanosine; C058118:2'-deoxyadenosine; D013936:Thymidine