Introduction to Relativistic Quantum Chemistry (original) (raw)

This page intentionally left blank 1. This postulate is usually presented as an independent postulate in most texts, but in fact postulate 2 follows from postulate 1, as shown by Frank and Rothe (1911). 1. This is not the conventional definition; is often used for the d'Alembertian. The current definition is appropriate for our purposes, in which we need a notation for both the four-vector and its square. 1. Some texts use e for the charge rather than q. However, we will always use e for the elementary charge and develop equations for the electron, whose charge is −e. 1. We write the matrix elements of the one-particle Hamiltonian with a lower case h, regardless of the case of the operator. Upper case H is reversed for many-particle Hamiltonian matrix elements. 1. The relations in (7.22) are only defined up to a phase, which we are free to choose. We have already chosen a phase factor of i to multiply the small component, so we choose a phase factor of 1 in this case.