@article {
author = {Li, Jing and Li, Xueliang and Lian, Huishu},
title = {Extremal skew energy of digraphs with no even cycles},
journal = {Transactions on Combinatorics},
volume = {3},
number = {1},
pages = {37-49},
year = {2014},
publisher = {University of Isfahan},
issn = {2251-8657},
eissn = {2251-8665},
doi = {10.22108/toc.2014.4059},
abstract = {Let $D$ be a digraph with skew-adjacency matrix $S(D)$. Then the skew energy of $D$ is defined as the sum of the norms of all eigenvalues of $S(D)$. Denote by $\mathcal{O}_n$ the class of digraphs of order $n$ with no even cycles, and by $\mathcal{O}_{n,m}$ the class of digraphs in $\mathcal{O}_n$ with $m$ arcs. In this paper, we first give the minimal skew energy digraphs in $\mathcal{O}_n$ and $\mathcal{O}_{n,m}$ with $n-1\leq m\leq \frac{3}{2}(n-1)$. Then we determine the maximal skew energy digraphs in $\mathcal{O}_{n,n}$ and $\mathcal{O}_{n,n+1}$, and in the latter case we assume that $n$ is even.},
keywords = {skew energy,digraph,signless matching polynomial,Characteristic polynomial},
url = {https://toc.ui.ac.ir/article_4059.html},
eprint = {https://toc.ui.ac.ir/article_4059_ed37714018ee8fbea9af32b692471f46.pdf}
}