{"title":"Modeling nanoparticle aggregation","authors":"S. Jungblut, A. Eychmüller","doi":"10.1039/9781788015868-00001","DOIUrl":"https://doi.org/10.1039/9781788015868-00001","url":null,"abstract":"The process of nanoparticle aggregation into highly porous structures is ubiquitous in nature and plays a crucial role in a number of nanotechnological applications, for instance, in the aerogel production. The details of the macroscopic structure assembled by the nanoparticles depend on the type of the inter-particle connections initiating the process. This chapter provides an overview of current investigations analyzing the effects which various types of inter-particle interactions have on the composition of the nanoparticle networks. Furthermore, it summarizes the methods applied to study reversible and irreversible network formation in computer simulations.","PeriodicalId":189225,"journal":{"name":"Chemical Modelling","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125094739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Aldongarov, A. M. Assilbekova, I. Irgibaeva, N. Barashkov
{"title":"Modeling electronic excitations/formation of trap states in semiconducting nanocrystals","authors":"A. Aldongarov, A. M. Assilbekova, I. Irgibaeva, N. Barashkov","doi":"10.1039/9781788015868-00173","DOIUrl":"https://doi.org/10.1039/9781788015868-00173","url":null,"abstract":"In this chapter we review recent results of modelling of formation of trap states and ideas on the optimal way of passivation based on these results. Passivation of quantum dots is a crucial condition determining their optical properties. Dangling bonds on the surface of nanocrystals were commonly considered as the main source of trap states. Recent studies clearly indicate that presence of dangling bonds not always lead to formation of trap states. We also present a new idea on formation of trap states, which considers the effect of the ground state dipole moment. Results obtained via density functional theory calculations indicate the correlation between the dipole moment value and formation of deep trap states. A correlation between the dipole moment value and the deepness of the trap states locations was demonstrated using the Cd4S cluster as a model basis and different number of SH groups as passivating agents. Namely, the high values of the dipole moment provide a higher number of trap states. Rearrangement of the same number of SH groups also indicates the dipole moment's effect on the electronic spectra. The application of an electrostatic field oriented against the dipole moment vector also confirms the importance of the dipole moment in formation of optical properties of nanocrystals.","PeriodicalId":189225,"journal":{"name":"Chemical Modelling","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127535742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Paths of chemical reactions and their networks: from geometry optimization to automated search and systematic analysis","authors":"Y. Sumiya, S. Maeda","doi":"10.1039/9781788015868-00028","DOIUrl":"https://doi.org/10.1039/9781788015868-00028","url":null,"abstract":"Reaction paths obtained through quantum chemical calculations have helped to understand reactivity and selectivity of many chemical reactions. Therefore, techniques for obtaining reaction paths have been one of the indispensable tools in modern computational chemistry. There have been considerable efforts in developing such computational techniques as introduced in this chapter. Moreover, there are methods that can find many paths automatically and generate a so-called reaction path network. Such automated reaction path search methods are also described in this chapter. Resultant reaction path networks may consist of hundreds or more of reaction paths, and it becomes hard to see the whole picture of such a complex network by human eyes. Hence, some kinetic theories are also presented as tools to analyse such a complex reaction path network. In the latter half of this chapter, actual reaction path networks are explained. At first, the size of the reaction path network depending on the number of atoms and elements included is discussed. Then, reaction path networks constructed by a specific reaction path search method are showcased. Simple systems are chosen as illustrative examples, and their reaction path networks are analysed systematically using a kinetic theory. Ways to study paths of nonadiabatic transitions are also discussed briefly. Finally, the chapter is summarized, and future perspectives are discussed. We hope that this chapter will help readers grasping the current state-of-the-art methodologies concerning paths of chemical reactions and their networks.","PeriodicalId":189225,"journal":{"name":"Chemical Modelling","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126104768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Charge transport through nanocontacts","authors":"Anup Pramanik, S. Sarkar, P. Sarkar","doi":"10.1039/9781788015868-00070","DOIUrl":"https://doi.org/10.1039/9781788015868-00070","url":null,"abstract":"The present chapter deals with the charge transport phenomena through different nanocontacts, involving pristine and doped/defective graphenes and molecular contacts formed by single molecules anchored in between metal surfaces. We discuss on the basic principles of mesoscopic charge transport, experimental and theoretical procedures and present some important results that we have obtained from first principle calculations. We also provide a brief review on the concerned area. For the graphene-based contacts, we put emphasis on the doped and defective graphene nanoribbons of different edge-symmetries and edge-passivations. Some nanocontacts have been formed by molecular pentacene, Ni-bis(dithiolene) complexes, carbon atomic nanowires, etc. The observed phenomena such as negative differential resistance, Schottky contact, etc. have been correlated with the electronic structures of the molecules and the graphene leads. The edge-states of graphene have been shown to have a great impact on the charge transport properties of the nanojunctions. The molecular contacts have been studied to show the conductance and carrier switching involving them. We have shown how stereoelectronic effects can lead to conductance switching in some specified σ-conjugated oligosilanes. Effects of conjugation length and chemical substitution have been shown to provide charge carrier switching in some nanojunctions.","PeriodicalId":189225,"journal":{"name":"Chemical Modelling","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116281637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Jaccob, M. Sankaralingam, Neethinathan Johnee Britto
{"title":"Activation of small molecules by transition-metal complexes","authors":"M. Jaccob, M. Sankaralingam, Neethinathan Johnee Britto","doi":"10.1039/9781788015868-00131","DOIUrl":"https://doi.org/10.1039/9781788015868-00131","url":null,"abstract":"","PeriodicalId":189225,"journal":{"name":"Chemical Modelling","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125576641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
