Akira Ikuo

Development of Electronic Lab-book for College Chemistry-Experiment - SN1 a SN2 Reactions -.

We developed a computer graphics (CG) teaching material (TM) for university students, concerning reactions involving drastic changes in the structure of the reactants in the following chlorination, for example SN1: formation of tert-butyl chloride from tert-butanol and SN2: formation of 1-chlorobutane from 1-butanol. The CG-TM could clearly demonstrate the changes in the structures during the reaction by the ball-and-stick model, in addition to the image of the energy change in terms of the reaction profile. An electronic lab-book for chemical experiments in the students’ laboratory at the university was produced, aiming at the integration of observable-level experiments, symbolic chemical equations, and the molecular world. The lab-book displays pictures of apparatus, flow-chart of experimental procedures, and reaction mechanisms with the CG-TM. A preliminary study on the effectiveness of the CG-TM suggested that students were able to obtain images of SN1 and SN2 reactions.

An Approach to Developing Electronic Textbook for Chemical Experiment - Taking Walden’s Inversion as an Example

We are developing electronic textbook for of basic chemistry-experiment for university students in which reaction mechanisms are shown by computer graphics (CG). The CGs of chemical reactions was made based on the empirical molecular orbital calculations. The CGs include following reactions as a model of Walden’s inversion where drastic change in structure takes place, such as, formation of 2-butyl alcohol and 1-butyl bromide. The CGs could simultaneously demonstrates the nature of the reaction such as structural change by the space-filling model and by the ball-and-stick model in addition to providing image of energy change by the reaction profile. The electronic textbook also displays picture of apparatus and flow-chart of small-scale experiment. Result of preliminary study on effectiveness of the CG is included.

Visualization of Chemical Reaction Based on Quantum Calculation for Teaching Material—Addition of Halogens to Cyclopentene

Teaching material by visualization of the reaction mechanism of halogenation of cyclopentene was made for students to understand and realize the nature of the chemical reaction. The reaction in the gas phase was studied by B3LYP/LanL2DZ level quantum calculation. The calculation revealed that the reaction with halogen radical via homolytic dissociation of halogen molecule is preferred compared with halogen ions via heterolytic dissociation of halogen molecule. The results were visualized in diagrams with the geometries of atoms on molecular structures and potential energies of reactants, intermediate compounds, and products. The lesson using the diagrams was carried out in an undergraduate physical chemistry laboratory class of junior (third year) level students of teacher’s college, Tokyo Gakugei University. Students’ attitudes and answers to questionnaire suggested that they realized the nature of halogenation somewhat smoothly. Their answers overall revealed that the lesson using the visualized diagrams was one of the influential methodologies for enhancing students’ understanding and grasp of the nature of the chemical reaction.

An Approach to Developing Electronic Laboratory Textbook—Experimental Program of Esterification of Acetic Acid and Ethanol

A computer graphics (CG) teaching material of the esterification of acetic acid and ethyl alcohol was made based on the quantum chemistry calculation. The CG teaching material could simultaneously display realistic shapes and electrostatic potentials of the molecules on the way from the state of reactants to that of products. The teaching material could demonstrate images of dynamical reaction mechanism of the esterification. We have integrated the teaching material with the laboratory manual of chemical experiments for University students to develop an electronic textbook. The textbook in the tablet PC could display not only experimental procedure but also the reaction mechanism by the CG teaching material.

Visualization of thermodynamic behaviour of Na + cation and Cl − anion based on quantum calculation for teaching material

Visualization of thermodynamic behaviour of Na+ cation and Cl- anion was made for teaching-materials creation from the viewpoint of thermodynamics for the student of university or high school level based on a quantum calculation by ab-initio-molecular orbital method. Original Born-Haber cycle including thermodynamic states of Na+ cation and Cl- anion in the dissolution of sodium chloride NaCl are proposed accompanying by construction drawing of molecules from the viewpoint of relative size and stoichiometry, and the intelligible diagrams with changes of entropy and Gibbs function about the dissolution are further introduced for student readily to understand the meaning of thermodynamic changes in the behaviour.

CG Teaching materials based on quantum chemical calculation for basic chemistry — An approach to the electronic textbook of basic chemistry linking chemical experiments

Change in the molecular configuration of transition states after the π-complex in benzene nitration made visible from the semi-empirical molecular orbital calculation. CG Teaching material could demonstrate the structural change of reactants with both space filling and ball-and-stick models along with the reaction profile, which can provide image of energy change during the reaction. The teaching material was tried to combine with chemical experiments of students lab used tablet PC for the purpose of making electronic textbook of basic chemistry, which integrates the observable level experiment and the molecular world.

Calculation of Potential Energy in the Reaction of “F + HCl → HF + Cl” and its Visualization

Geometries and potential energies (PE) for intermediates of “F-H-Cl” around the transition state in the reaction of “F + HCl → HF + Cl” were calculated, and computer graphics (CGs) of PE in two-dimension (2-D) and PE surface in three-dimension (3-D), skeletal structures of intermediates on the way of the reaction, and the reaction profile were created. CG animation composed of four CGs was proposed in order to express images of the reaction.