Theoretical Studies of Chemical Interactions. Ab Initio Calculations on Lithium Dialkylamides and Their Carbonylation Reactions

1994 ◽  
Vol 116 (22) ◽  
pp. 10110-10116 ◽  
Author(s):  
P. Viruela-Martin ◽  
R. Viruela-Martin ◽  
F. Tomas ◽  
N. S. Nudelman
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Theoretical Studies ◽  
Chemical Interactions

scholarly journals Combined Experimental and Theoretical Studies: Lattice-Dynamical Studies at High Pressures with the Help of Ab Initio Calculations

Minerals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1283
Author(s):  
Francisco Javier Manjón ◽  
Juan Ángel Sans ◽  
Placida Rodríguez-Hernández ◽  
Alfonso Muñoz
Keyword(s):  
Raman Scattering ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Phase Change Materials ◽  
High Pressures ◽  
Complete Characterization ◽  
Vibrational Properties ◽  
Theoretical Studies ◽  
Experimental And Theoretical Studies

Lattice dynamics studies are important for the proper characterization of materials, since these studies provide information on the structure and chemistry of materials via their vibrational properties. These studies are complementary to structural characterization, usually by means of electron, neutron, or X-ray diffraction measurements. In particular, Raman scattering and infrared absorption measurements are very powerful, and are the most common and easy techniques to obtain information on the vibrational modes at the Brillouin zone center. Unfortunately, many materials, like most minerals, cannot be obtained in a single crystal form, and one cannot play with the different scattering geometries in order to make a complete characterization of the Raman scattering tensor of the material. For this reason, the vibrational properties of many materials, some of them known for millennia, are poorly known even under room conditions. In this paper, we show that, although it seems contradictory, the combination of experimental and theoretical studies, like Raman scattering experiments conducted at high pressure and ab initio calculations, is of great help to obtain information on the vibrational properties of materials at different pressures, including at room pressure. The present paper does not include new experimental or computational results. Its focus is on stressing the importance of combined experimental and computational approaches to understand materials properties. For this purpose, we show examples of materials already studied in different fields, including some hot topic areas such as phase change materials, thermoelectric materials, topological insulators, and new subjects as metavalent bonding.

scholarly journals Theoretical studies on the intramolecular cyclization of 2,4,6-t-Bu3C6H2P=C: and effects of conjugation between the P=C and aromatic moieties

2014 ◽  
Vol 10 ◽  
pp. 1032-1036 ◽  
Author(s):  
Masaaki Yoshifuji ◽  
Shigekazu Ito
Keyword(s):  
Activation Energy ◽  
Dft Calculations ◽  
Physicochemical Properties ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Intramolecular Cyclization ◽  
Theoretical Studies ◽  
Cyclization Product ◽  
No Activation

The intramolecular C–H insertion of the Mes*-substituted phosphanylidenecarbene [Mes*P=C:] (Mes* = 2,4,6-t-Bu3C6H2) and physicochemical properties of the cyclized product, 6,8-di-tert-butyl-3,4-dihydro-4,4-dimethyl-1-phosphanaphthalene were studied based on ab initio calculations. Whereas the alternative Fritsch–Buttenberg–Wiechell-type rearrangement requires almost no activation energy, the intramolecular cyclization needs an activation energy of 12.3 kcal/mol at the MP2(full)/6-31G(d) condition. DFT calculations supported that the optimized structure of the cyclization product of Mes*P=C: suggests remarkable conjugation effects between the nearly coplanar P=C skeleton and the aryl moiety.

Theoretical Studies on the Effect of N-Substitution on the Hydrogen Bonds of Metal Ion/Water/Amide Complexes

1984 ◽  
Vol 39 (7) ◽  
pp. 686-691
Author(s):  
Kritsana P. Sagarik ◽  
Bernd M. Rode
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonds ◽  
Metal Ions ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Metal Ion ◽  
Basis Set ◽  
Theoretical Studies ◽  
Backbone Atoms ◽  
Atomic Populations

The effect of N-substitution on the hydrogen bonds of metal ion/water/amide complexes is studied on Li+/N-methylformamide-water as an example. Using the energies and Mulliken atomic populations derived from ab initio calculations with minimal GLO basis set, the Li+/Nmethyl formamide-water and Li+/formamide-water complexes are compared. The transference of the effect of metal ions along the molecular structure seems to have a profound relationship to the bond polarizabilities of the backbone atoms. This can be discussed qualitatively in terms of changes in the Mulliken atomic publications.

Theoretical Studies on the Pyridine−I2Charge-Transfer Complex. 1. Ab-Initio Calculations on I2and Pyridine−I2

1997 ◽  
Vol 101 (24) ◽  
pp. 4409-4415 ◽  
Author(s):  
Stephan Reiling ◽  
Marcel Besnard ◽  
Philippe A. Bopp
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Theoretical Studies

Acquiring a record barrier height for magnetization reversal in lanthanide encapsulated fullerene molecules using DFT and ab initio calculations

2016 ◽  
Vol 52 (97) ◽  
pp. 14047-14050 ◽  
Author(s):  
Mukesh Kumar Singh ◽  
Gopalan Rajaraman
Keyword(s):  
Excited State ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Barrier Height ◽  
Magnetization Reversal ◽  
Theoretical Studies ◽  
First Excited State

Theoretical studies on DyOM@Cxy (M = Lu and Sc, xy = 72, 76(1–4) and 82) clusters encapsulating six EMFs suggest relaxation via the first excited state in most of the DyOLu@Cxy (except DyOLu@C82) and via the fourth excited state in all the DyOSc@Cxy EMFs with extremely large Ucal values.

Sign in / Sign up

Export Citation Format

Share Document