of boron-hydride bonding configurations. Wandering atoms was a puzzle solved by Lipscomb in one of his few papers with no co-authors. Compounds of boron and hydrogen tend to form closed cage structures. Sometimes the atoms at the vertices of these cages move substantial distances with respect to each other. The diamond-square-diamond mechanism (diagram at left) was suggested by Lipscomb to explain this rearrangement of vertices. Following along in the diagram at left for example in the faces shaded in blue, a pair of triangular faces has a left-right diamond shape. First, the bond common to these adjacent triangles breaks, forming a square, and then the square collapses back to an up-down diamond shape by bonding the atoms that were not bonded before. Other researchers have discovered more about these rearrangements. The B10H16 structure (diagram at right) determined by Grimes, Wang, Lewin, and Lipscomb found a bond directly between two boron atoms without terminal hydrogens, a feature not previously seen in other boron hydrides. Lipscomb's group developed calculation methods, both empirical and from quantum mechanical theory. Calculations by these methods produced accurate Hartree–Fock self-consistent field (SCF) molecular orbitals and were used to study boranes and carboranes. The ethane barrier to rotation (diagram at left) was first calculated accurately by Pitzer and Lipscomb using the Hartree–Fock (SCF) method. Lipscomb's calculations continued to a detailed examination of partial bonding through "... theoretical studies of multicentered chemical bonds including both delocalized and localized molecular orbitals." This included "... proposed molecular orbital descriptions in which the bonding electrons are delocalized over the whole molecule." "Lipscomb and his coworkers developed the idea of transferability of atomic properties, by which approximate theories for complex molecules are developed from more exact calculations for simpler but chemically related molecules,..." Subsequent Nobel Prize winner Roald Hoffmann was a doctoral student in Lipscomb's laboratory. Under Lipscomb's direction the Extended Hückel method of molecular orbital calculation was developed by Lawrence Lohr and by Roald Hoffmann. This method was later extended by Hoffman. In Lipscomb's laboratory this method was reconciled with self-consistent field (SCF) theory by Newton and by Boer. Noted boron chemist M. Frederick Hawthorne conducted early and continuing research with Lipscomb. Much of this work is summarized in a book by Lipscomb, Boron Hydrides, one of Lipscomb's two books. The 1976 Nobel Prize in Chemistry was awarded to Lipscomb "for his studies on the structure of boranes illuminating problems of chemical