Coordination computer programs

GF method calculations are simplified by the systematic behavior of the G matrix elements (Decius 1948). MUBFF calculations, however, are somewhat complicated by the force constants representing interactions between non-bonded atoms— these can be tedious to express in terms of internal coordinates. Computer programs have been written to partially automate calculations, thereby reducing the necessary effort and minimizing opportunities for errors (e.g., Schachtschneider 1964 Gale and Rohl 2003). 

In clinical trials that solely or partially rely on paper forms and pure paper-based data collection systems, participating sites use a mail carrier to send batches of hard copies of completed forms to the coordinating center. With this approach to data, forms and computer programs are necessary to keep track of received batches of completed forms. 

These are invariant to translation and rotation of a stereomodel. Most experimental chemists are familiar with internal coordinates from crystal structure analyses and the employment of molecular modelling computer programs. With regard to fundamental concepts of stereochemistry, internal coordinates are of prime importance as they allow clear definitions of terms to be formulated. ... 

Write a computer program that finds the principal moments and principal axes of inertia for a molecule. Do not use matrix diagonalization instead, solve the secular equation by using the formula for the roots of a cubic equation. The input to the program is the set of atomic masses and coordinates in an arbitrary system with axes not necessarily at the center of mass. 

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