×

Mixed graphs with \(H\)-rank 3. (English) Zbl 1361.05076

Summary: B. Mohar [ibid. 489, 324–340 (2016; Zbl 1327.05215)] determined all mixed graphs with \(H\)-rank 2, and used it to classify cospectral graphs with respect to their Hermitian adjacency matrix, constructing a class of graphs which can not be determined by their \(H\)-spectrum. In the present paper, we investigate the \(H\)-rank of mixed graphs further, determining the \(H\)-ranks of those mixed graphs with trees, cycles and complete bipartite graphs as underlying graphs, respectively. Moreover, we characterize all mixed graphs with \(H\)-rank 3, and show that all connected mixed graphs with \(H\)-rank 3 can be determined by their \(H\)-spectrum.

MSC:

05C50 Graphs and linear algebra (matrices, eigenvalues, etc.)

Citations:

Zbl 1327.05215
Full Text: DOI

References:

[1] Cheng, B.; Liu, B.-L., On the nullity of graphs, Electron. J. Linear Algebra, 16, 60-67 (2007) · Zbl 1142.05336
[2] Cheng, G.-J.; Huang, L.-H.; Yeh, H.-G., A characterization of graphs with rank 4, Linear Algebra Appl., 434, 8, 1793-1798 (2011) · Zbl 1216.05071
[3] Cheng, G.-J.; Huang, L.-H.; Yeh, H.-G., A characterization of graphs with rank 5, Linear Algebra Appl., 436, 11, 4241-4250 (2012) · Zbl 1241.05062
[4] Cvetković, D.; Gutman, I., Application of Graph Spectra (2009), Matematički institut SANU · Zbl 1166.05002
[5] van Dam, E. R.; Haemers, W. H., Which graphs are determined by their spectrum?, Special Issue on the Combinatorial Matrix Theory Conference. Special Issue on the Combinatorial Matrix Theory Conference, Pohang, 2002. Special Issue on the Combinatorial Matrix Theory Conference. Special Issue on the Combinatorial Matrix Theory Conference, Pohang, 2002, Linear Algebra Appl., 373, 241-272 (2003) · Zbl 1026.05079
[6] van Dam, E. R.; Haemers, W. H., Developments on spectral characterization of graphs, Discrete Math., 309, 3, 576-586 (2009) · Zbl 1205.05156
[7] Liu, J.-X.; Li, X.-L., Hermitian-adjacency matrices and hermitian energies of mixed graphs, Linear Algebra Appl., 466, 182-207 (2015) · Zbl 1302.05106
[8] Guo, K.; Mohar, B., Hermitian adjacency matrix of digraphs and mixed graphs · Zbl 1365.05173
[9] Mohar, B., Hermitian adjacency spectrum and switching equivalence of mixed graphs, Linear Algebra Appl., 489, 324-340 (2016) · Zbl 1327.05215
[10] Petrović, M.; Radosavljević, Z., Spectrally Constrained Graphs (2001), Faculty of Science: Faculty of Science Belgrade
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.