We propose a multiconfiguration density functional combining a short-range density functional approximation with a novel long-range correction for dynamic correlation effects. The correction is derived from the adiabatic connection formalism so that the resulting functional requires access only to one- and two-electron reduced density matrices of the system. In practice, the functional is formulated for wavefunctions of the complete active space (CAS) type and the short-range density functional part is made dependent on the on-top pair density via auxiliary spin densities. The latter allows for reducing the self-interaction and the static correlation errors without breaking the spin symmetry. We study the properties and the performance of the non-self-consistent variant of the method, termed lrAC0-postCAS. Numerical demonstration on a set of dissociation energy curves and excitation energies shows that lrAC0-postCAS provides accuracy comparable with more computationally expensive ab initio rivals.
An injectable hydrogel formulation is developed utilizing low‐ and high‐molecular‐weight chitosan (LCH and HCH) incorporated with curcumin and α‐tocopherol‐loaded liposomes (Lip/Cur+Toc). Cur and Toc releases are delayed within the hydrogels. The injectability of hydrogels is proved via rheological analyses. In vitro studies are conducted using human dental pulp stem cells (hDPSCs) and human gingival fibroblasts (hGFs) to examine the biological performance of the hydrogels toward endodontics and periodontics, respectively. The viability of hDPSCs treated with the hydrogels with Lip/Cur+Toc is the highest till day 14, compared to the neat hydrogels. During odontogenic differentiation tests, alkaline phosphatase (ALP) enzyme activity of hDPSCs is induced in the Cur‐containing groups. Biomineralization is enhanced mostly with Lip/Cur+Toc incorporation. The viability of hGFs is the highest in HCH combined with Lip/Cur+Toc while wound healing occurs almost 100% in both (Lip/Cur+Toc@LCH and Lip/Cur+Toc@HCH) after 2 days. Antioxidant activity of Lip/Cur+Toc@LCH on hGFs is significantly the highest among the groups. Antimicrobial tests demonstrate that Lip/Cur+Toc@LCH is more effective against Escherichia coli whereas so is Lip/Cur+Toc@HCH against Staphylococcus aureus. The antimicrobial mechanism of the hydrogels is investigated for the first time through various computational models. LCH and HCH loaded with Lip/Cur+Toc are promising candidates with multi‐functional features for endodontics and periodontics.
19 May 2022 in Journal of Chemical Theory and Computation
We address the problem of intermolecular interaction energy calculations in molecular complexes with localized excitons. Our focus is on the correct representation of the dispersion energy. We derive an extended Casimir-Polder formula for direct computation of this contribution through second order in the intermolecular interaction operator V̂. An alternative formula, accurate to infinite order in V̂, is derived within the framework of the adiabatic connection (AC) theory. We also propose a new parametrization of the VV10 nonlocal correlation density functional, so that it corrects the CASSCF energy for the dispersion contribution and can be applied to excited-state complexes. A numerical investigation is carried out for benzene, pyridine, and peptide complexes with the local exciton corresponding to the lowest π-π* or n- π* states. The extended Casimir-Polder formula is implemented in the framework of multiconfigurational symmetry-adapted perturbation theory, SAPT(MC). A SAPT(MC) analysis shows that the creation of a localized exciton affects mostly the electrostatic component of the interaction energy of investigated complexes. Nevertheless, the changes in Pauli repulsion and dispersion energies cannot be neglected. We verify the performance of several perturbation- and AC-based methods. Best results are obtained with a range-separated variant of an approximate AC approach employing extended random phase approximation and CASSCF wave functions.