Equilibrium solvation in quadrupolar solvents.
نویسندگان
چکیده
We present a microscopic theory of equilibrium solvation in solvents with zero dipole moment and nonzero quadrupole moment (quadrupolar solvents). The theory is formulated in terms of autocorrelation functions of the quadrupolar polarization (structure factors). It can be therefore applied to an arbitrary dense quadrupolar solvent for which the structure factors are defined. We formulate a simple analytical perturbation treatment for the structure factors. The solute is described by coordinates, radii, and partial charges of constituent atoms. The theory is tested on Monte Carlo simulations of solvation in model quadrupolar solvents. It is also applied to the calculation of the activation barrier of electron transfer reactions in a cleft-shaped donor-bridge-acceptor complex dissolved in benzene with the structure factors of quadrupolar polarization obtained from molecular-dynamics simulations.
منابع مشابه
On the validity of dielectric continuum models in application to solvation in molecular solvents
We report Monte Carlo simulations of solvation of a point dipole in dipolar–quadrupolar solvents of varying dipole moment and axial quadrupole. The simulations are carried out to test the prediction of dielectric solvation models of a monotonic increase of the absolute value of the solvation chemical potential umpu with the solvent dielectric constant e . Dielectric constants are obtained from ...
متن کاملThree pulse photon echo studies of nondipolar solvation: Comparison with a viscoelastic model
Three pulse stimulated photon echo peak shift ͑3PEPS͒ measurements were used to probe the solvation of a quadrupolar solute in three room temperature nondipolar solvents; benzene, CCl 4 , and CS 2 , and the results were compared with those for two polar solvents, methanol and acetonitrile, and one weakly polar solvent, toluene. Our data reveal three distinct solvent dynamical time scales; a sub-1...
متن کاملDirect Visualization of Excited-State Symmetry Breaking Using Ultrafast Time-Resolved Infrared Spectroscopy.
Most symmetric quadrupolar molecules designed for two-photon absorption behave as dipolar molecules in the S1 electronic excited state. This is usually explained by a breakup of the symmetry in the excited state. However, the origin of this process and its dynamics are still not fully understood. Here, excited-state symmetry breaking in a quadrupolar molecule with a D-π-A-π-D motif, where D and...
متن کاملDipolar Solvation Dynamics
The dynamics of solvation of newly created dipoles is discussed. Developments of standard continuum models to include non-Debye dielectric response and saturation effects are described. Equilibrium and non-equilibrium molecular-dynamics simulations of ST2 model water are described. The simulations predict non-exponential solvation dynamics as a result of the radial dependence of the solvent res...
متن کاملCollective water dynamics in the first solvation shell drive the NMR relaxation of aqueous quadrupolar cations.
Using molecular simulations, we analyze the microscopic processes driving the Nuclear Magnetic Resonance (NMR) relaxation of quadrupolar cations in water. The fluctuations of the Electric Field Gradient (EFG) experienced by alkaline and magnesium cations, which determine the NMR relaxation time, are mainly due to the dynamics of water molecules in their solvation shell. The dynamics of the ion ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of chemical physics
دوره 123 4 شماره
صفحات -
تاریخ انتشار 2005