4. Coping with Smallness and Scanning Probe Microscopy
Richard M. Colgate Professor of Chemistry
This lecture critiques early attempts at atomic visualization by charlatans, then examines experiments by Newton and Franklin for measuring small distances. It concludes by detailing the principles and applications of Scanning Probe Microscopy for probing individual molecules and atoms.
Freshman Organic Chemistry (CHEM 125)
This lecture asks whether it is possible to confirm the reality of bonds by seeing or feeling them. It first describes the work of "clairvoyant" charlatans from the beginning of the twentieth century, who claimed to "see" details of atomic and molecular structure, in order to discuss proper bases for scientific belief. It then shows that the molecular scale is not inconceivably small, and that Newton and Franklin performed simple experiments that measure such small distances. In the last 25 years various realizations of Scanning Probe Microscopy have enabled chemists to "feel" individual molecules and atoms, but not bonds.
3. Double Minima, Earnshaw's Theorem and Plum-Puddings
Next · Lecture 55. X-Ray Diffraction