Search results for "Van der Waals"
showing 3 items of 203 documents
Phonons in MoSe2/WSe2 van der Waals heterobilayer
2021
We report first-principles calculations of the structural and vibrational properties of the synthesized two-dimensional van der Waals heterostructures formed by single-layers dichalcogenides MoSe2 and WSe2. We show that, when combining these systems in a periodic two-dimensional heterostructures, the intrinsic phonon characteristics of the free-standing constituents are to a large extent preserved but, furthermore, exhibit shear and breathing phonon modes that are not present in the individual building blocks. These peculiar modes depend strongly on the weak vdW forces and has a great contibution to the thermal properties of the layered materials. Besides these features, the departure of fl…
Evidence of Weak Halogen Bonding: New Insights on Itraconazole and its Succinic Acid Cocrystal
2012
Exact knowledge of the crystal structure of drugs and lead compounds plays a significant role in the fields of crystal engineering, docking, computational modeling (drug–receptor interactions), and rational design of potent drugs in pharmaceutical chemistry. The succinic acid cocrystal of the systemic antifungal drug, itraconazole, reported by Remenar et al. (J. Am. Chem. Soc.2003, 125, 8456–8457) (CSD: IKEQEU), represents one of the classical examples displaying a molecular fitting mechanism in the solid state. In this work, we disclose the X-ray single-crystal structure of the cis-itraconazole–succinic acid (2:1) cocrystal and found that it differs slightly from the previously reported st…
Etude théorique de surfaces d'énergie potentielle, de moment dipolaire et de polarizabilité des complexes de van der Waals CH4-N2 et C2H4-C2H4
2010
In the present thesis both ab initio and analytical calculations were carried out for thepotential energy, dipole moment and polarizability surfaces of the weakly bound van der Waals complexes CH4-N2 and C2H4-C2H4 for a broad range of intermolecular separations and configurations in the approximation of the rigid interacting molecules. For ab initio calculations the CCSD(T), CCSD(T)-F12 and less computationally expensive methods such as MP2, MP2-F12, SAPT, DFT-SAPT were employed (for all methods the aug-cc-pVTZ basis set was used). The BSSE correction was taken into account during the calculations. The analytical calculations were performed in the framework of the classical long-range appro…