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Most philosophers of science have believed that chemistry has been reduced to physics and is of no fundamental interest, but they have begun to realize that the central science of chemistry has been overlooked. Educators in chemistry, textbook writers and designers of instructional software know that part of the art of chemistry teaching is in knowing how to balance the unifying principles and the more apparently diverse qualitative/descriptive aspects. Axiomatizing chemistry seems not well founded based on relative lack of rigorous mathematical theories in chemical sciences. Laws of chemistry differ from typical laws of physics. Recurrence of elements after certain intervals is approximate and the repeat period varies. Realism and orbitals are discussed. Content and not the learning process might be a better approach for the direction of chemical education research.

The interface and dopant disorders in delta-doped grid-gate gallium arsenide quantum-dot devices have been studied using three-dimensional self-consistent simulation. The largest variation in device behavior seems to be caused by change in dopant number, not potential fluctuations. Electron population in the quantum well cannot screen the much larger potential spike.

Intrinsic chaos in a dc field-biased quantum heterostructure is discussed. A closed quantum, double barrier, GaAs/AlGaAs heterostructure is chaotic as a result of addition of a nonlinear potential term to the time-dependent Schrodinger equation. The dynamical behavior of an electron cloud moving in the heterostrucure biased by a dc electric field is examined numerically.

Methods that will improve performance of the multiquantum well stack in optical modulator devices based on quantum-confined Stark effect can be found from observing that effective mass of the active quantum well material is significantly smaller in the conduction band than in the valence band. Significant improvements could then be likely to be found in the overall performance of the devices that likely would be achieved by engineering the band alignment of quantum well and barrier to accommodate differences in effective masses. A band-alignment strategy for efficient optical modulation in quantum-confined Stark effect devices is presented.