Various spectral aspects of NCCC-graphs of certain finite non-abelian groups

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Document Type : Research Paper

Authors

1 Department of Mathematical Science, Tezpur University, Napaam-784028, Sonitpur, Assam, India. Department of Mathematics, Assam Engineering Institute, Chandmari, Guwahati-781003, Assam, India.

2 Department of Mathematical Science, Tezpur University, Napaam-784028, Sonitpur, Assam, India. Discipline of Mathematics, K. K. Handiqui State Open University, Khanapara, Guwahati-781022, India.

3 Department of Mathematical Science, Tezpur University, Napaam-784028, Sonitpur, Assam, India.

10.22034/as.2026.23008.1785

Abstract

Let ${G}$ be a finite non-abelian group. The non-commuting conjugacy class graph (abbreviated as NCCC-graph) of $G$ is a simple undirected graph whose vertex set is the set of conjugacy classes of non-central elements of $G$ and two vertices $x^G$ and $y^G$ are adjacent to each other if $x'$ and $y'$ do not commute for all $x'\in x^G$ and $y'\in y^G$, where $x^G$ is the conjugacy class of $x \in G$. In this paper, we compute the spectrum, Laplacian spectrum, signless Laplacian spectrum and corresponding energies of NCCC-graphs of certain families of finite non-abelian groups. We determine whether these graphs are integral, L-integral and Q-integral. Further, we compare energy, Laplacian energy and signless Laplacian energy; and determine whether these graphs are borderenergetic, L-borderenergetic, Q-borderenergetic, hyperenergetic, L-hyperenergetic or Q-hyperenergetic.

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References

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Algebraic Structures and Their Applications

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Available Online from 07 October 2026

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