Excited state dynamics of some nonsteroidal anti-inflammatory drugs: A surface-hopping investigation

Abstract

Here we present a computational investigation of the excited state dynamics of 5 different active medical substances (aspirin, ibuprofen, carprofen, suprofen, indomethacin) which belong to the family of nonsteroidal anti-inflammatory drugs (NSAIDs). The nonadiabatic dynamics simulations were performed using the surface hopping method, with electronic energies and couplings evaluated on the fly in a semiempirical framework. For aspirin, the solvent decay dynamics was also considered by inserting it in a cluster of water molecules, following a QM/MM scheme. A quite diverse behavior was observed for the systems considered, going from fast deactivation to the S 0 (aspirin and ibuprofen), to ultrafast intersystem crossing to the triplet manifold (carprofen and suprofen), or to the generation of long lived S 1 states (indomethacin). To our knowledge, this is the first computational study of the photodynamics of these NSAIDs.

Photochemistry in the strong coupling regime: A trajectory surface hopping scheme

“…[ 60–62 ] For the time evolution of the polaritonic wavefunction, we adopt the local diabatization technique, [ 48,63 ] with a recently improved evaluation of transition probabilities. Such probabilities are compliant with Tully's Fewest Switches prescription and particularly effective when many states are involved in nonadiabatic events, [ 64 ] as commonly happens in single‐molecule polaritonic systems (see Figure 1b).…”

Surface Hopping Dynamics with the Frenkel Exciton Model in a Semiempirical Framework

“…We adopt the local diabatization (LD) formalism 21 , 23 , 25 , 27 for the integration of the electronic time-dependent Schrödinger equation in the surface hopping scheme. It requires the evaluation of the wavefunction overlaps at each time step along the nuclear trajectory.…”

“…11 If instead the Coulomb coupling terms are computed exactly by eq 6, we perform the corresponding approximation of evaluating ∇V ai,bj , considering only the static contribution to the derivative (i.e., only the gradient of the two-electron integrals in the AO basis is evaluated, while the gradient of the density matrices is neglected). We adopt the local diabatization (LD) formalism 21,23,25,27 for the integration of the electronic time-dependent Schrodinger equation in the surface hopping scheme. It requires the evaluation of the wavefunction overlaps…”

Quantum and semiclassical dynamical studies of nonadiabatic processes in solution: achievements and perspectives

“…However, some extra effort may be required in reparamaterizing the semiempirical Hamiltonian, as they are typically optimized for ground state rather than excited state computations. 166 The FOMO method has been used in on-the-fly dynamics calculations with different applications, 11,166,178,179,[182][183][184][185][186][187][188] some of them paying special attention to the role of solvent in the photodynamics. For example, simulations of azobenzene in vacuo, n-hexane, methanol and in ethylene glycol revealed that a delay in isomerization was predicted to depend more on the size and mass of the solvent molecules than on the intermolecular interactions, being fastest in vacuo, intermediate in methanol and hexane, and slowest in ethylene glycol.…”