CALCULATION OF BASIC PARAMETERS NECESSARY FOR QUANTUM CHEMICAL CALCULATIONS ON BORON-CONTAINING MOLECULES. 1. ONE-CENTER ELECTRON REPULSION INTEGRAL (PP/PP)B

The research results of the modification of the properties of the optical inorganic materials, such as: optical ceramic КО1(MgF2) and КО2(ZnS) have been presented. Essential change of the basic parameters of these inorganic matrixes, which surface has been modified with the carbon nanotubes under the application of the laser oriented deposition technique, has been established. The main features of the carbon nanotubes have been taken into account, which have been connected with their branched surface, large hardness of the C-C bonds and small value of the refractive index. Analytical and quantum-chemical calculations as well as the experimental results have been presented, which have been connected with the change of the spectral, mechanical and wetting characteristics of the chosen inorganic matrixes.

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Towards Quantitative Evaluation of Charge Transfer in Insulating Material: Examination based on Quantum Chemical Calculations

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.135.618 ◽

2015 ◽

Vol 135 (10) ◽

pp. 618-623

Author(s):

Masahiro Sato ◽

Akiko Kumada ◽

Kunihiko Hidaka

Keyword(s):

Charge Transfer ◽

Quantum Chemical Calculations ◽

Quantitative Evaluation ◽

Quantum Chemical ◽

Insulating Material

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Discovery of a Difluoroglycine Synthesis Method through Quantum Chemical Calculations

10.26434/chemrxiv.11550057.v1 ◽

2020 ◽

Author(s):

Tsuyoshi Mita ◽

Yu Harabuchi ◽

Satoshi Maeda

Keyword(s):

Quantum Chemical Calculations ◽

Experimental Verification ◽

Quantum Chemical ◽

Synthesis Method ◽

Target Product ◽

Systematic Exploration ◽

Hands On ◽

Retrosynthetic Analysis ◽

Synthetic Routes ◽

Verification Process

The systematic exploration of synthetic pathways to afford a desired product through quantum chemical calculations remains a considerable challenge. In 2013, Maeda et al. introduced ‘quantum chemistry aided retrosynthetic analysis’ (QCaRA), which uses quantum chemical calculations to search systematically for decomposition paths of the target product and propose a synthesis method. However, until now, no new reactions suggested by QCaRA have been reported to lead to experimental discoveries. Using a difluoroglycine derivative as a target, this study investigated the ability of QCaRA to suggest various synthetic paths to the target without relying on previous data or the knowledge and experience of chemists. Furthermore, experimental verification of the seemingly most promising path led to the discovery of a synthesis method for the difluoroglycine derivative. The extent of the hands-on expertise of chemists required during the verification process was also evaluated. These insights are expected to advance the applicability of QCaRA to the discovery of viable experimental synthetic routes.

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Discovery of a Difluoroglycine Synthesis Method through Quantum Chemical Calculations

10.26434/chemrxiv.11550057 ◽

2020 ◽

Author(s):

Tsuyoshi Mita ◽

Yu Harabuchi ◽

Satoshi Maeda

Keyword(s):

Quantum Chemical Calculations ◽

Experimental Verification ◽

Quantum Chemical ◽

Synthesis Method ◽

Target Product ◽

Systematic Exploration ◽

Hands On ◽

Retrosynthetic Analysis ◽

Synthetic Routes ◽

Verification Process

The systematic exploration of synthetic pathways to afford a desired product through quantum chemical calculations remains a considerable challenge. In 2013, Maeda et al. introduced ‘quantum chemistry aided retrosynthetic analysis’ (QCaRA), which uses quantum chemical calculations to search systematically for decomposition paths of the target product and propose a synthesis method. However, until now, no new reactions suggested by QCaRA have been reported to lead to experimental discoveries. Using a difluoroglycine derivative as a target, this study investigated the ability of QCaRA to suggest various synthetic paths to the target without relying on previous data or the knowledge and experience of chemists. Furthermore, experimental verification of the seemingly most promising path led to the discovery of a synthesis method for the difluoroglycine derivative. The extent of the hands-on expertise of chemists required during the verification process was also evaluated. These insights are expected to advance the applicability of QCaRA to the discovery of viable experimental synthetic routes.

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The Nature of Chemisorbed CO2 in Zeolite A

10.26434/chemrxiv.7422815 ◽

2019 ◽

Author(s):

Przemyslaw Rzepka ◽

Zoltán Bacsik ◽

Andrew J. Pell ◽

Niklas Hedin ◽

Aleksander Jaworski

Keyword(s):

Solid State ◽

Ir Spectroscopy ◽

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Surface Coverage ◽

Gas Mixtures ◽

Mas Nmr ◽

Significant Fraction ◽

Zeolite A

Formation of CO32- and HCO3- species without participation of the framework oxygen atoms upon chemisorption of CO2 in zeolite |Na12|-A is revealed. The transfer of O and H atoms is very likely to have proceeded via the involvement of residual H2O or acid groups. A combined study by solid-state 13C MAS NMR, quantum chemical calculations, and in situ IR spectroscopy showed that the chemisorption mainly occurred by the formation of HCO3-. However, at a low surface coverage of physisorbed and acidic CO2, a significant fraction of the HCO3- was deprotonated and transformed into CO32-. We expect that similar chemisorption of CO2 would occur for low-silica zeolites and other basic silicates of interest for the capture of CO2 from gas mixtures.

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Mechanistic Investigation of Rh(I)-Catalyzed Asymmetric Suzuki-Miyaura Coupling with Racemic Allyl Halides

10.26434/chemrxiv.8208617.v1 ◽

2019 ◽

Cited By ~ 2

Author(s):

Lucy van Dijk ◽

Ruchuta Ardkhean ◽

Mireia Sidera ◽

Sedef Karabiyikoglu ◽

Özlem Sari ◽

...

Keyword(s):

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Experimental Studies ◽

Mechanistic Investigation ◽

Allyl Halides

A mechanism for Rh(I)-catalyzed asymmetric Suzuki-Miyaura coupling with racemic allyl halides is proposed based on a combination of experimental studies and quantum chemical calculations.

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