Lower Bounds for Gaussian Estrada Index of Graphs

Suppose that G is a graph over n vertices. G has n eigenvalues (of adjacency matrix) represented by λ1, λ2, · · · , λn. The Gaussian Estrada index, denoted by H(G) (Estrada et al., Chaos 27(2017) 023109), can be defined as H(G) = ∑ i=1 e −λi . Gaussian Estrada index underlines the eigenvalues close to zero, which plays an important role in chemistry reactions, such as molecular stability and molecular magnetic properties. In a network of particles governed by quantum mechanics, this graph-theoretic index is known to account for the information encoded in the eigenvalues of the Hamiltonian near zero by folding the graph spectrum. In this paper, we establish some new lower bounds for H(G) in terms of the number of vertices, the number of edges, as well as the first Zagreb index.

[1]  Yilun Shang,et al.  LOWER BOUNDS FOR THE ESTRADA INDEX OF GRAPHS , 2012 .

[2]  Bo Zhou,et al.  ON ESTRADA INDEX , 2008 .

[3]  Muhammad Kamran Siddiqui,et al.  Computing Zagreb Indices and Zagreb Polynomials for Symmetrical Nanotubes , 2018, Symmetry.

[4]  Werner Kutzelnigg,et al.  What I like about Hückel theory , 2007, J. Comput. Chem..

[5]  Ernesto Estrada,et al.  Characterization of the folding degree of proteins , 2002, Bioinform..

[6]  Ernesto Estrada Characterization of the amino acid contribution to the folding degree of proteins , 2004, Proteins.

[7]  I. Gutman,et al.  NULLITY OF GRAPHS: AN UPDATED SURVEY , 2010 .

[8]  J. A. Rodríguez-Velázquez,et al.  Subgraph centrality in complex networks. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[9]  A LOWER BOUND FOR THE ESTRADA INDEX OF BIPARTITE MOLECULAR GRAPHS , 2007 .

[10]  Shang Yi-Lun Local Natural Connectivity in Complex Networks , 2011 .

[11]  Yilun Shang,et al.  Lower bounds for the Estrada index , 2012 .

[12]  J. A. Peña,et al.  Estimating the Estrada index , 2007 .

[13]  Ivan Gutman,et al.  LOWER BOUNDS FOR ESTRADA INDEX , 2008 .

[14]  Ernesto Estrada Characterization of 3D molecular structure , 2000 .

[15]  María Robbiano,et al.  On the Diameter and Incidence Energy of Iterated Total Graphs , 2018, Symmetry.

[16]  Yilun Shang,et al.  Estrada Index of Random Bipartite Graphs , 2015, Symmetry.

[17]  Lin-wang Wang,et al.  Solving Schrödinger’s equation around a desired energy: Application to silicon quantum dots , 1994 .

[18]  Bo Zhou On the spectral radius of nonnegative matrices , 2000, Australas. J Comb..

[19]  Yilun Shang,et al.  The Estrada index of evolving graphs , 2015, Appl. Math. Comput..

[20]  I. Gutman,et al.  Graph theory and molecular orbitals. Total φ-electron energy of alternant hydrocarbons , 1972 .

[21]  Yilun Shang,et al.  ESTRADA INDEX OF GENERAL WEIGHTED GRAPHS , 2013 .

[22]  J. A. Rodríguez-Velázquez,et al.  Atomic branching in molecules , 2006 .

[23]  Yilun Shang,et al.  Biased edge failure in scale-free networks based on natural connectivity , 2012 .

[24]  Mauricio Barahona,et al.  Robustness of regular ring lattices based on natural connectivity , 2011, Int. J. Syst. Sci..

[25]  J. A. Rodríguez-Velázquez,et al.  Spectral measures of bipartivity in complex networks. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[26]  D. Cvetkovic,et al.  Recent Results in the Theory of Graph Spectra , 2012 .

[27]  Ernesto Estrada,et al.  Exploring the "Middle Earth" of Network Spectra via a Gaussian Matrix Function , 2016, Chaos.