Publications
Sort:
Open Access Research Article Issue
Spectra of quasi-corona and multiple Q-complemented-vertex join graphs
AIMS Mathematics 2026, 11(4): 10205-10225
Published: 15 April 2026
Abstract PDF (282.7 KB) Collect
Downloads:7

The Q-complemented graph of a graph G, denoted by C T ( G ), was obtained by adding a new vertex for each edge u v E ( G ), where this new vertex was adjacent to all vertices of G except u and v. In this paper, we introduced two new graph constructions based on C T ( G ), namely, the quasi-corona Q-complemented-vertex join G 1 G 2 and the multiple Q-complemented-vertex join G 1 G 2 . We determined the adjacency, Laplacian, and signless Laplacian spectra of these composite graphs. Using these spectral results, we constructed infinite families of A-, L-, and Q-cospectral graphs. Moreover, we derived explicit formulas for several key invariants of the new graphs, including the number of spanning trees, the Kirchhoff index, the signless Laplacian energy-like invariant, and graph energy. Furthermore, numerical experiments were provided to illustrate the structural properties of the proposed graphs, suggesting that the multiple Q-complemented-vertex join construction may exhibit certain small-world-like characteristics.

Total 1