研究目的

Investigating the ground and excited electronic state properties of seven isomers of 2-aminopyridine (2AMP) stacked dimer.

研究成果

The interaction energy values for seven isomers of the stacked dimer of 2AMP, calculated using the est. CCSD(T) method with CBS limit, were found to be in the range of -7.7 kcal/mol to -4.9 kcal/mol. The most stable dimer has two weak N???H interactions. Among several DFT functionals tested, B3LYP-D3 and B97D yielded excellent ?Eint values that were comparable to that of the est. CCSD(T)/CBS method, with a mean absolute deviation of ~ 0.3 kcal/mol. For the ten lowest excited states, TDDFT computations were carried out and the resulting vertical excitation energy values were compared with those of the RI-CC2/def2-TZVP method. The M06-2X and CAM-B3LYP functionals yielded results in good agreement with those of the RICC2, giving a mean absolute deviation of 0.1 eV. The influence of solvents (water and acetonitrile) on the vertical excitation energy values was found to be negligible. It becomes clear that upon excitation of (2AMP)2, the N???H bond length increases and deactivation occurs from the state S1 to S0 via internal conversion.

研究不足

The technical and application constraints of the experiments, as well as potential areas for optimization, are not explicitly mentioned in the paper.