scholarly journals Closed Neighborhood Degree Sum-Based Topological Descriptors of Graphene Structures

2021 ◽  
Vol 12 (5) ◽  
pp. 7111-7124
Keyword(s):  
Topological Descriptors ◽  
Degree Sum ◽  
Chemical Structures ◽  
Closed Neighborhood ◽  
Graphene Structures

Topological descriptors defined on chemical structures enable understanding the properties and activities of chemical molecules. In this paper, we compute closed neighborhood degree sum-based indices for four different Graphene structures. The cardinality of closed neighborhood degree-based edge partitions for four different Graphene structures is used to compute the closed neighborhood degree sum-based indices.

scholarly journals Topological Analysis of PAHs using Irregularity based Indices

2021 ◽  
Vol 12 (3) ◽  
pp. 2970-2987
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Topological Analysis ◽  
Chemical Properties ◽  
Topological Descriptors ◽  
Graph Invariants ◽  
Chemical Structures ◽  
Potential Applications ◽  
Polycyclic Aromatic ◽  
Analytical Expressions

Topological descriptors are non-empirical graph invariants that characterize the structures of chemical molecules. The structural descriptors are vital components of QSAR/QSPR studies which form the basis for theoretical chemists to design and investigate new chemical structures. Irregularity indices are a class of topological descriptors that have been employed to study certain chemical properties of compounds. This article aims to compute analytical expressions of irregularity indices for three important classes of polycyclic aromatic hydrocarbons. The intriguing properties of these classes of compounds have several potential applications in wide-raging fields, which warrant a study of their properties from a structural perspective. Additionally, the 3D graphical representations of a few indices are presented, which will aid in analyzing the similarity of behavior among the indices.

Topological properties of Sierpinski network and its application

2021 ◽  
Vol 24 ◽  
Author(s):  
Juanyan Fang ◽  
Muhammad Rafiullah ◽  
Hafiz Muhammad Afzal Siddiqui
Keyword(s):  
Biological Activity ◽  
Thermodynamic Properties ◽  
Physicochemical Properties ◽  
Graphical Representation ◽  
Standard Procedure ◽  
Topological Descriptors ◽  
Fractal Nature ◽  
Eccentric Connectivity Index ◽  
Chemical Structures ◽  
3D Graphical Representation

Background: Sierpinski graphs S(n,k) are largely studied because of their fractal nature with applications in topology, chemistry, mathematics of Tower of Hanoi, and computer sciences. Applications of molecular structure descriptors are a standard procedure that are used to correlate the biological activity of molecules with their chemical structures and thus can be helpful in the field of pharmacology. Objective: The aim of this article is to establish analytically closed computing formulae for eccentricity-based descriptors of Sierpinski networks and their regularizations. These computing formulae are useful to determine a large number of properties like thermodynamic properties, physicochemical properties, chemical and biological activity of chemical graphs. Methods: At first, vertex sets have been partitioned on the basis of their degrees, eccentricities, and frequencies of occurrence. Then these partitions are used to compute the eccentricity-based indices with the aid of some combinatorics. Results: The total eccentric index and eccentric-connectivity index have been computed. We also compute some eccentricity-based Zagreb indices of the Sierpinski networks. Moreover, a comparison has also been presented in the form of graphs. Conclusion: These computations will help the readers to estimate the thermodynamic properties, physicochemical properties of chemical structures, which are of fractal nature and can not be dealt with easily. A 3D graphical representation is also presented to understand the dynamics of the aforementioned topological descriptors.

scholarly journals Multiplicative topological descriptors of Silicon carbide

2019 ◽  
Vol 4 (1) ◽  
pp. 181-190 ◽  
Author(s):  
Abaid ur Rehman Virk ◽  
Tanveer Abbas ◽  
Wasim Khalid
Keyword(s):  
Silicon Carbide ◽  
Topological Indices ◽  
Topological Descriptors ◽  
Mathematical Approach ◽  
Chemical Structures ◽  
Silicon Carbon

AbstractTopological indices helps us to collect information about algebraic graphs and gives us mathematical approach to understand the properties of chemical structures. In this paper, we aim to compute multiplicative degree-based topological indices of Silicon-Carbon Si2C3−III[p,q] and SiC3−III[p,q] .

scholarly journals Topological Descriptors of M-Carbon M r , s , t

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Hong Yang ◽  
Muhammad Naeem
Keyword(s):  
Crystal Structures ◽  
Topological Indices ◽  
Connectivity Index ◽  
Topological Descriptors ◽  
Chemical System ◽  
Zagreb Indices ◽  
Chemical Structures ◽  
The One ◽  
Atom Bond

We have studied topological indices of the one the hardest crystal structures in a given chemical system, namely, M-carbon. These structures are based and obtained by the famous algorithm USPEX. The computations and applications of topological indices in the study of chemical structures is growing exponentially. Our aim in this article is to compare and compute some well-known topological indices based on degree and sum of degrees, namely, general Randić indices, Zagreb indices, atom bond connectivity index, geometric arithmetic index, new Zagreb indices, fourth atom bond connectivity index, fifth geometric arithmetic index, and Sanskruti index of the M-carbon M r , s , t . Moreover, we have also computed closed formulas for these indices.

scholarly journals On ve-degree- and ev-degree-based topological properties of crystallographic structure of cuprite Cu2O

2021 ◽  
Vol 19 (1) ◽  
pp. 576-585
Author(s):  
Shu-Bo Chen ◽  
Abdul Rauf ◽  
Muhammad Ishtiaq ◽  
Muhammad Naeem ◽  
Adnan Aslam
Keyword(s):  
Graph Theory ◽  
Copper Oxide ◽  
Topological Indices ◽  
Topological Descriptors ◽  
Crystallographic Structure ◽  
Chemical Substances ◽  
Chemical Graph ◽  
Chemical Structures ◽  
Chemical Graph Theory ◽  
Enormous Number

Abstract In the study of chemical graph theory, an enormous number of research analyses have confirmed that the characteristics of chemicals have a nearby connection with their atomic structure. Topological indices were the critical tools for the analysis of these chemical substances to consider the essential topology of chemical structures. Topological descriptors are the significant numerical quantities or invariant in the fields of chemical graph theory. In this study, we have studied the crystal structure of copper oxide ( Cu 2 O {{\rm{Cu}}}_{2}{\rm{O}} ) chemical graph, and further, we have calculated the ev-degree- and ve-degree-based topological indices of copper oxide chemical graph. This kind of study may be useful for understanding the atomic mechanisms of corrosion and stress–corrosion cracking of copper.

scholarly journals Computing Topological Descriptors and Polynomials of Certain 2D Chemical Structures

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Muhammad Mubashir Izhar ◽  
Zahida Perveen ◽  
Dalal Alrowaili ◽  
Mehran Azeem ◽  
Imran Siddique ◽  
...  
Keyword(s):  
Environmental Chemistry ◽  
Molecular Descriptor ◽  
Molecular Graph ◽  
Analytical Framework ◽  
Topological Indices ◽  
Topological Descriptors ◽  
Zagreb Index ◽  
Chemical Structures ◽  
Nylon 6,6 ◽  
The First Zagreb Index

In the fields of mathematical chemistry, a topological index, also known as a connectivity index, is a type of a molecular descriptor that is calculated based on the molecular graph of a chemical compound. Topological indices are an analytical framework of a graph which portray its topology and are mostly equal graphs. Topological indices (TIs) are numeral quantities that are used to foresee the natural correlation among the physicochemical properties of the chemical compounds in their fundamental network. TIs show an essential role in the theoretical abstract and environmental chemistry and pharmacology. In this paper, we compute many latest developed degree-based TIs. An analogy among the computed different versions of the TIs with the help of the numerical values and their graphs is also included .In this article, we compute the first Zagreb index, second Zagreb index, hyper Zagreb index, ABC Index, GA Index, and first Zagreb polynomial and second Zagreb polynomial of chemical graphs polythiophene, nylon 6,6, and the backbone structure of DNA.

scholarly journals Computation of Vertex-Based Topological Descriptors of Organometallic Monolayers of TM 3 C 12 S 12

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Dalal Alrowaili ◽  
Faraha Ashraf ◽  
Rifaqat Ali ◽  
Arsalan Shoukat ◽  
Aqila Shaheen ◽  
...  
Keyword(s):  
Quantitative Structure Activity Relationship ◽  
Topological Descriptors ◽  
Quantitative Structure ◽  
Structure Property ◽  
Biological Structure ◽  
Qsar Modeling ◽  
Chemical Structures ◽  
Structure Activity ◽  
Structure Property Relationship ◽  
Mathematical Relationships

Topological descriptors are mathematical values related to chemical structures which are associated with different physicochemical properties. The use of topological descriptors has a great contribution in the field of quantitative structure-property relationship (QSPR) and quantitative structure-activity relationship (QSAR) modeling. These are mathematical relationships between different molecular properties or biological activity and some other physicochemical or structural properties. In this article, we calculate few vertex degree-based topological indices/descriptors of the organometallic monolayer structure. At present, the numerical programming of the biological structure with topological descriptors is increasing in consequence in invigorating science, bioinformatics, and pharmaceutics.

Chemical structure of diamond-like carbon thin films

1990 ◽  
Vol 48 (4) ◽  
pp. 710-711
Author(s):  
N.-H. Cho ◽  
K.M. Krishnan ◽  
D.B. Bogy
Keyword(s):  
Electrical Resistivity ◽  
Chemical Structure ◽  
Diamond Like Carbon ◽  
Chemical Structures ◽  
Sputtering Power ◽  
Data Aquisition ◽  
Equilibrium Phases ◽  
Electron Energy Loss ◽  
Power Densities ◽  
Preparation Techniques

Diamond-like carbon (DLC) films have attracted much attention due to their useful properties and applications. These properties are quite variable depending on film preparation techniques and conditions, DLC is a metastable state formed from highly non-equilibrium phases during the condensation of ionized particles. The nature of the films is therefore strongly dependent on their particular chemical structures. In this study, electron energy loss spectroscopy (EELS) was used to investigate how the chemical bonding configurations of DLC films vary as a function of sputtering power densities. The electrical resistivity of the films was determined, and related to their chemical structure.DLC films with a thickness of about 300Å were prepared at 0.1, 1.1, 2.1, and 10.0 watts/cm2, respectively, on NaCl substrates by d.c. magnetron sputtering. EEL spectra were obtained from diamond, graphite, and the films using a JEOL 200 CX electron microscope operating at 200 kV. A Gatan parallel EEL spectrometer and a Kevex data aquisition system were used to analyze the energy distribution of transmitted electrons. The electrical resistivity of the films was measured by the four point probe method.

Chemical Structures and their Properties of Wood Components

2013 ◽  
Vol 67 (10) ◽  
pp. 1131-1136
Author(s):  
Toshiyuki Takano
Keyword(s):  
Chemical Structures
Sign in / Sign up

Export Citation Format

Share Document