Addition to “Practical Training in Simple Hückel Theory: Matrix Diagonalization via Tridiagonalization, Cyclobutadiene, and Visualization of Molecular Orbitals”

This paper is an addition to the article "Practical Training in Simple Huckel Theory: Matrix Diagonalization for Highly Symmetric Molecules and Visualization of Molecular Orbitals" by Shin-ichi Nagaoka, Tatsunobu Kokubo, Hiroyuki Teramae, and Umpei Nagashima.(l). Yoshinori Yamasaki, from the Department of Mathematics, Faculty of Science and Graduate School of Science and Engineering, Ehime University, Matsuyama 790-8577, Japan, is an author of this addition, together with the authors of the original article. With the addition, the new title of this work is "Practical Training in Simple Huckel Theory: Matrix Diagonalization via Tridiagonalization, Cyclobutadiene, and Visualization of Molecular Orbitals".