A Fortran IV program has been written to aid in the characterization of new materials and especially coordination complexes and nonstoichiometric substances, through comparison between the observed and calculated elemental analyses. Through an iterative procedure the program assimilates the microanalytical data, i.e., elemental analysis, and/or molecular weight, and the synthetic components, e.g., the metal, ligands, counter ions, and solvents, and prints all the possible formulations which fit the analytical data within prescribed tolerances. In addition a variety of tolerances are supplied by the user to render the program quite flexible, e.g., for the microanalysis, molecular weight, and empirical formula. The program is currently available for use with a remote terminal; however, slight modification will permit use with batch jobs.During research projects dealing with inorganic and organic compounds, it becomes necessary to synthesize and characterize a relatively large number of coordination compounds containing metal ions and organic coordinating agents (ligands).Part of the characterization procedure involves the determination of the empirical formulas of the synthesized complexes, and among the data used in these determinations are the microanalyses (usually for carbon, hydrogen, nitrogen, metal, and/or other elements).Since the same microanalytical data might be indicative of two or more empirical formulas, it was decided that rather than attempting to deduce by hand all the possible formulations which could apply to a given set of microanalytical data, it would be appropriate to develop a computer program which would automatically determine these formulations. It was decided to include a sizable degree of flexibility in the program so that a research scientist would be able to utilize it for as many as seven different chemical units {e.g., a ligand, a metal ion, solvent molecule, anion, etc.) and as many as eight different elements in one compound. Further, the program permits the researcher to set the tolerances by which the calculated percent composition of the hypothetical compounds described by the computer may vary from the actual microanalyses, and he may instruct the computer to print the empirical formulas of all combinations of possible chemical units in the compound which are within the permissible deviation from the actual microanalyses (with a maximum of 99.9 chemical units per compound and a maximum of 99 atoms of one element in a chemical unit.) Additionally, the computer is instructed to print the elemental percentages, molecular weight, formula of and empirical formula and their deviation for each element from the actual microanalyses. Furthermore, the standard deviations for each hypothetical formulation are listed so that comparisons between hypothetical formulations are facilitated.This computer program has already proved valuable in identifying all of the hypothetical compounds which conform to a given microanalysis within reasonably small deviations.1-2'3 With this information, it i...