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Immanants and immanantal polynomials of chemical graphs
1Office of Pollution Prevention and Toxics, Risk Assessment Division (7403M), US Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC 20460, USA. cash.gordon@epa.gov
Abstract:
The much-studied determinant and characteristic polynomial and the less well-known permanent and permanental polynomial are special cases of a large class of objects, the immanants and immanantal polynomials. These have received some attention in the mathematical literature, but very little has appeared on their applications to chemical graphs. The present study focuses on these and also generalizes the acyclic or matching polynomial to an equally large class of acyclic immanantal polynomials, generalizes the Sachs theorem to immanantal polynomials, and sets forth relationships between the immanants and other graph properties, namely, Kekulé structure count, number of Hamiltonian cycles, Clar covering polynomial, and Hosoya sextet polynomial.
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