Quantum mechanics/molecular mechanics studies on mechanistic photophysics of cytosine aza-analogues: 2,4-diamino-1,3,5-triazine and 2-amino-1,3,5-triazine in aqueous solution

Abstract

The excited-state properties and photophysics of cytosine aza-analogues, i.e., 2,4-diamino-1,3,5-triazine (2,4-DT) and 2-amino-1,3,5-triazine (2-AT) in solution have been systematically explored using the QM(MS-CASPT2//CASSCF)/MM approach. The excited-state nonradiative relaxation mechanisms for...

Quantum mechanics/molecular mechanics studies on the excited-state decay mechanisms of cytidine aza-analogues: 5-azacytidine and 2′-deoxy-5-azacytidine in aqueous solution

“…1), and a similar system setup strategy can be found in our previous works. 15,[26][27][28][29][30] In the computations of MM minimizations and MD simulations, the solute 5ACyd and 5AdCyd molecules are adopted with the prepared and modified CHARMM22 force field parameters and the solvent water molecules are described by the TIP3P model, respectively. [31][32][33] All MM computations are performed by means of the DL_POLY module of the CHEMSHELL3.5 package.…”