A new spectral graph invariant spr(R), called Randic spread, is defined and investigated. This quantity is equal to the maximal difference between two eigenvalues of the Randic matrix, disregarding the spectral radius. Lower bounds for spr(R) are deduced, some of which depending on the Randi index of the underlying graph. (Joint work with H. Gomes, I. Gutman, M. Robbiano, B. San Martín.)
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