The D-eigenvalues of a graph G are the eigenvalues of its distance matrix D, and the
D-energy ED(G) is the sum of the absolute values of its D-eigenvalues. Two graphs are
said to be D-equienergetic if they have the same D-energy. In this note we obtain bounds
for the distance spectral radius and D-energy of graphs of diameter 2. Pairs of equiregular
D-equienergetic graphs of diameter 2, on p = 3t + 1 vertices are also constructed.