A computational extension of a theory whose name begins with this term relaxes the “strong orthogonality condition” from Coulson–Fischer theory. An initial assumption in a theory whose name begins with this term that precluded the “charge-shift” family led to the failure to explain the antiaromaticity of cyclobutadiene. That theory whose name begins with this term arose from Walter Heitler and Fritz London’s solution to the Schrödinger equation for diatomic hydrogen, which was then expanded upon in a 1939 textbook by Linus Pauling. The AXE (“A-X-E”) method is used in a formalism beginning with this term that assigns labels such (10[1])as “T-shaped” and “seesaw.” For 10 points, (10[1]-5[1])molecular (-5[1])geometries are described using the “electron pair repulsion” of what outermost electrons in an (10[1])atom? (10[2])■END■ (10[1])