Molecular orbital configurations give rise to electronic terms comprising corresponding electronic states. Electronic terms possess symmetry classifications, which are denoted by a term symbol, based on the symmetry properties of the electronic wave functions associated with the states. Using the methylene radical, and both planar and twisted…

Introductory chemistry students encounter the concept of hybrid orbitals as a transition from atomic orbitals to molecular bonding. The principal purpose of learning hybridization in the undergraduate curriculum is to impart an understanding of the origins of molecular bonding and geometry. Physical models of both individual hybrid orbitals and…

The goal of this study was to investigate the timing of online homework completion and its effects on student performance. Data was collected from two large, first-semester general chemistry sections at a southwestern university. Specifically, this study aims to explore the link between when students complete their homework relative to the date…

The ever-increasing impact of molecular quantum calculations over chemical sciences implies a strong and urgent need for the elaboration of proper teaching strategies in university curricula. In such perspective, this paper proposes an extensive project for a student-driven, cooperative, from-scratch implementation of a general Hartree-Fock…

Both, virtual and printed 3D crystal models can help students and teachers deal with chemical education topics such as symmetry and point groups. In the present paper, two freely downloadable tools (interactive PDF files and a mobile app) are presented as examples of the application of 3D design to study point-symmetry. The use of 3D printing to…

A system for construction of simple poster-board models is described. The models dynamically demonstrate the symmetry operations of proper rotation, improper rotation, reflection, and inversion for the chemically important point groups D[subscript 3h], D[subscript 4h], D[subscript 5h], D[subscript 6h], T[subscript d], and O[subscript h]. The…

The first introduction to molecular geometry should be through the simple and easily understood VSEPR model, as the Valence Bond Theory and MO Theory suffer from limitations as far as understanding molecular geometry is concerned. The VSEPR model gives a perfectly satisfactory description of the bonding that follows directly from the Lewis model…

Packing efficiency and crystal density can be calculated from basic geometric principles employing the Pythagorean theorem, if the unit-cell structure is known. The procedures illustrated have applicability in courses such as general chemistry, intermediate and advanced inorganic, materials science, and solid-state physics.

Chemical bonding, for most simple complexes, is described in the Mulliken-Walsh Molecular Orbital (MO) theory. (CP)

Reviews graphical methods for representing ternary and quaternary systems, focusing on use of triangular composition diagrams. Examines some of the relevant geometry of triangles in general, showing that right isosceles triangles possess some very advantageous features for representing ternary systems. (JN)