the stacking mechanism of the 1h-4h proton transfer in 4-pyridone, 4-pyridinthione and p-aminopyridineare constructed. for quantitative description of this process by means of the quamtumchemicalmethod density functional theory (dft) the activation energy (

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Kohn-Sham density functional theory (KS-DFT)[1, 2] is an efficient and usefully accurate electronic structure method, because it replaces the interacting Schrödinger equation with a set of single-particle orbital equations. Calculations with several hundred atoms are now routine, but there is always interest in much larger systems. Many such systems are treated by a lower-level method, such as ...

The response of an extended periodic system to a homogeneous field ~of wave-vector q50) cannot be obtained from a q50 time-dependent density functional theory ~TDDFT! calculation, because the RungeGross theorem does not apply. Time-dependent current–density functional theory is needed and demonstrates that one key ingredient missing from TDDFT is the macroscopic current. In the low-frequency li...

Article history: Received 19 April 2008 Received in revised form 2 June 2008 Accepted 15 July 2008 Available online 19 July 2008 PACS: 71.15.-m 71.15.Mb 71.15.Dx

We have studied the medium effects on the frequency-dependent polarizability of water by separating the total polarizability of water clusters into polarizabilities of the individual water molecules. A classical frequency-dependent dipole–dipole interaction model based on classical electrostatics and an Unsöld dispersion formula has been used. It is shown that the model reproduces the polarizab...

In this work we investigated by density functional theory (DFT)/time-dependent DFT (TDDFT) supramolecular complexes for photoinitiated electron collection, in particular [{(bpy)2Ru(dpp)}2RhCl2] and related catalysts derived by variation of the ligand/metal. The electron collection in this class of catalysts enables hydrogen production or DNA cleavage, among other applications. Changes in excita...