ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAb initio calculations on the very strong hydrogen bond of biformate anion and comparative esterification studiesJ. Emsley, O. P. A. Hoyte, R. E. OverillCite this: J. Am. Chem. Soc. 1978, 100, 11, 3303–3306Publication Date (Print):May 1, 1978Publication History Published online1 May 2002Published inissue 1 1978https://pubs.acs.org/doi/10.1021/ja00479a008https://doi.org/10.1021/ja00479a008research-articleACS PublicationsRequest reuse...

An initio SCF perturbation theory in the formulation of Ditchfield and Snyder has been applied to calculation N.M.R. spin-spin coupling constants CH4, NH3, H2O HF using large gaussian basis sets, including all second-order contributions (Fermi contact, orbital dipolar). In accordance with most other work, first-order term contribution neglected, however. The sensitivity variations set studied, reliability method is discussed light these results. It shown that Fermi contact provides largest...

Journal Article Foundations of Cryptography: Basic Tools Get access Richard E. Overill Search for other works by this author on: Oxford Academic Google Scholar Logic and Computation, Volume 12, Issue 3, June 2002, Pages 543–544, https://doi.org/10.1093/logcom/12.3.543-a Published: 01 2002

The number of alleged crimes in computer networks had not increased until a few years ago. Real-time analysis has become essential to detect any suspicious activities. Network classification is the first step network traffic analysis, and it core element intrusion detection systems (IDS). Although techniques have improved their accuracy been enhanced, growing trend encryption insistence application developers create new ways avoid applications being filtered detected are among reasons that...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAn unexpectedly strong hydrogen bond: ab initio calculations and spectroscopic studies of amide-fluoride systemsJohn Emsley, Deborah J. Jones, Jack M. Miller, Richard E. Overill, Roland A. WaddiloveCite this: Am. Chem. Soc. 1981, 103, 1, 24–28Publication Date (Print):January 1981Publication History Published online1 May 2002Published inissue 1 January...

The retail sector often does not possess sufficient knowledge about potential or actual frauds. This requires the to employ an anomaly detection approach fraud detection. To detect anomalies in transactions, system introduced this work implements various salient features of human immune system. novel artificial system, called CIFD (computer for detection), adopts both negative selection and positive generate cells. also employs analogy self-major histocompatability complex (MHC) molecules...

Ab initio LCAO-MO-SCF calculations have been performed on the polyfluoride ions HnFn+1–, n= 1–4, and hydrogen fluoride polymers (HF)m, m= to determine their molecular configurations hydrogen-bond energies of polyfluorides. All polyfluorides are strongly bonded structures in which a central fluorine acts as acceptor one four HF molecules. The prefer open-chain arrangements. A safe simple method preparing K[HF2] high yield is given.

Ab initio LCAO–MO–SCF calculations have been performed on the acetic acid–fluoride system and strength of hydrogen bond, MeCO2H ⋯ F–, is found to be as strong that previously reported for formic system. The implications this its relationship other physical parameters these bonds are discussed. carboxylic systems capable forming esters with simple alkyl halides. enhanced nucleophilicity RCO2H has shown due increased negative charge hydroxy oxygen atom induced by formation very bond fluoride ion.

Experimental evidence for the structure of isoelectronic radical ions, C2H6 + and B2H6 -, is reviewed discussed. Recent E.S.R. data anion - are analysed results interpreted to favour a staggered D 3d rather than bridged 2h parent molecule. Ab initio unrestricted Hartree-Fock calculations after quartet state annihilation on support this conclusion.

Regardless of the established security controls that organizations have put in place to protect their digital assets, a rise insider threats has been observed and particularly incidents data leakage. The importance as corporate assets is leading growing need for detection, prevention mitigation such violations by organisations. In this paper we are investigating different types implications environment, with specific emphasis special case Organisations should evaluate risk they facing due...

The field of digital evidence must contend with an increasing number devices to be examined paralleled diversity. Examiners face a battle understand what artefacts may exist on these devices. Further, many current forensic tools look comprehensively examine sources which can generate large amounts of, often spurious, data no easy means correlation. This paper proposes the use ontology - Digital Evidence Semantic Ontology (DESO) that allows examiner quickly discover available device before...

J. Emsley, D. Jones and R. E. Overill, Chem. Soc., Commun., 1982, 476 DOI: 10.1039/C39820000476

Ab-initio UHF and complete Cl calculations using minimal basis sets of atomic orbitals have been made for the neutral radical BH2 isoelectronic series radicals N32–, NO2, CO2–, BO22–, BF2. The purpose is to test theoretically reliability an equation derived by Coulson linking bond angle with orbital hybridisation on central atom. It concluded that this qualitatively reliable.