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Frontier

A slim hole rig weighs about one fifth of a conventional rig and its small size can open new frontiers by making exploration economic in environmentally sensitive or inaccessible areas. [Pg.52]

For an operation of seginentation, the vector d will have to be calculated that matrix allows to separate the noise of defects. We search transitions of frontiers, there is all couples (i, j) of pixels such that i is an intensity linked to the noise and j an intensity linked to the defect. [Pg.233]

A couple of pixels is included in the frontier between an object and the background of the image, if one of pixels belongs to the object and the other to the background. [Pg.234]

Ball P 1994 Designing the Moiecuiar Worid Chemistry at the Frontier (Phnceton, NJ Princeton University Press)... [Pg.81]

The liquid-solid interface, which is the interface that is involved in many chemical and enviromnental applications, is described m section A 1.7.6. This interface is more complex than the solid-vacuum interface, and can only be probed by a limited number of experimental techniques. Thus, obtaining a fiindamental understanding of its properties represents a challenging frontier for surface science. [Pg.284]

One of tlie less explored frontiers in atomic-scale surface science is the study of the liquid-solid interface. [Pg.314]

The current frontiers for the subject of non-equilibrium thennodynamics are rich and active. Two areas dommate interest non-linear effects and molecular bioenergetics. The linearization step used in the near equilibrium regime is inappropriate far from equilibrium. Progress with a microscopic kinetic theory [38] for non-linear fluctuation phenomena has been made. Carefiil experiments [39] confinn this theory. Non-equilibrium long range correlations play an important role in some of the light scattering effects in fluids in far from equilibrium states [38, 39]. [Pg.713]

Hocheimer H D and Etters R D 1991 Frontiers of High-Pressure Research (New York Pienum)... [Pg.1966]

We have surveyed tire remarkable progress in tire field of ET reactions, and have examined some of tire key applications and successes of tire tlieory. Many of tire current frontiers of ET research he in biological systems and in molecular-scale electronic devices. [Pg.2990]

Voth G A and Hoohstrasser R M 1996 Transition state dynamios and relaxation prooesses in solutions a frontier of physioal ohemistry J. Phys. Chem. 100 13034-49... [Pg.3049]

R. Englman and A. Yahalom, in TheJahn Teller Ejfect A Permanent Presence in the Frontiers of Science, M. D. Kaplan and G. Zimmerman, eds.. Proceedings of the NATO Advanced Research Workshop. Boston. Sept. 2000, Kluwer, Dordrecht, 2001. [Pg.170]

V. E. Taylor, R. L. Stevens and K. E. Arnold, Parallel molecular dynamics Communication requirements for massively parallel machines , Proc. Frontiers... [Pg.493]

Simple Approaches to Quantifying Chemical Reactivity 3.4.2.1 Frontier Molecular Orbital Theory... [Pg.179]

In view of this, early quantum mechanical approximations still merit interest, as they can provide quantitative data that can be correlated with observations on chemical reactivity. One of the most successful methods for explaining the course of chemical reactions is frontier molecular orbital (FMO) theory [5]. The course of a chemical reaction is rationali2ed on the basis of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), the frontier orbitals. Both the energy and the orbital coefficients of the HOMO and LUMO of the reactants are taken into account. [Pg.179]

The new bonds will be made between those two ends of the reactants where the orbital coefiicients of the frontier orbitals match best, where both have the largest coefficients. [Pg.179]

The importance of FMO theory hes in the fact that good results may be obtained even if the frontier molecular orbitals are calculated by rather simple, approximate quantum mechanical methods such as perturbation theory. Even simple additivity schemes have been developed for estimating the energies and the orbital coefficients of frontier molecular orbitals [6]. [Pg.179]

I. Fleming, Frontier Orbitals and Organic Chemical Reactions, Wiley, New York, 1976. [Pg.201]

Emphasis was put on providing a sound physicochemical basis for the modeling of the effects determining a reaction mechanism. Thus, methods were developed for the estimation of pXj-vahies, bond dissociation energies, heats of formation, frontier molecular orbital energies and coefficients, and stcric hindrance. [Pg.549]

Yon can use HyperChem to investigate the reactivity ofmoleciiles and their fiinciional groups. One method is to use Frontier Molec-... [Pg.8]

HOMO and LLMO, also known as Frontier orbitals, are important in in tcrprcLitig results of a calculation (see Frontier Molecular Orbitals on page 141). You can use these m olecular orbiLals to comptiLe the lowest excited electronic singlet state of molecules and the ground states of radicals. [Pg.42]

When you request an orbital, yon can use the cardinal number of the orbital (ordered by energy and starting with number=l) or an offset from either the highest occupied molecular orbital (HOMO) or the lowest unoccupied molecular orbital (LL MO). Offset from the HOMO are negative and from the LUMO are positive. Often these frontier orbitals are the ones of most chemical interest. [Pg.244]

Reuter N, A Dqaegere, B Maigret and M Karplus 2000. Frontier Bonds in QM/MM Methods j Comparison of Different Approaches. Journal of Physical Chemistry A104 1720-1733. [Pg.653]

The way the substituents affect the rate of the reaction can be rationalised with the aid of the Frontier Molecular Orbital (FMO) theory. This theory was developed during a study of the role of orbital symmetry in pericyclic reactions by Woodward and Hoffinann and, independently, by Fukui Later, Houk contributed significantly to the understanding of the reactivity and selectivity of these processes. ... [Pg.4]

Figure 1.3. Frontier orbital energies (eV) and confidents for acrolein and protonated acrolein. In the latter case the upper numbers refer to the situation where bond lengths and angles correspond to those of acrolein. The lower numbers are more suitable for a hydroxyallyl cation. The actual situation is assumed to be intermediate. The data are taken from ref. 104. Figure 1.3. Frontier orbital energies (eV) and confidents for acrolein and protonated acrolein. In the latter case the upper numbers refer to the situation where bond lengths and angles correspond to those of acrolein. The lower numbers are more suitable for a hydroxyallyl cation. The actual situation is assumed to be intermediate. The data are taken from ref. 104.
Note that the stereochemistry comes out right. H s a and b are cis because they were cis in the starting quinone and the Diels-Alder reaction is stereospecific in this respect. H is also cis to and H " because the Diels-Alder reaction is stereoselectively endo. These points are described in more detail in Norman p.284-6 and explained in Ian Fleming Frontier Orbitals and Organic Chemical Reactions, Wiley 1976, p. 106-109. How would you make diene A ... [Pg.70]

HOMO and LUMO energies FMO reactivity indices Refractivity Total energy Ionization potential Electron affinity Energy of protonation Orbital populations Frontier orbital densities Superdelocalizabilities... [Pg.245]


See other pages where Frontier is mentioned: [Pg.182]    [Pg.205]    [Pg.243]    [Pg.427]    [Pg.233]    [Pg.288]    [Pg.714]    [Pg.81]    [Pg.1382]    [Pg.2980]    [Pg.494]    [Pg.140]    [Pg.141]    [Pg.307]    [Pg.57]    [Pg.18]    [Pg.61]   
See also in sourсe #XX -- [ Pg.24 , Pg.25 , Pg.31 , Pg.47 , Pg.155 , Pg.156 , Pg.157 , Pg.158 , Pg.159 , Pg.160 , Pg.167 , Pg.199 , Pg.215 , Pg.216 , Pg.226 ]

See also in sourсe #XX -- [ Pg.110 ]

See also in sourсe #XX -- [ Pg.137 , Pg.185 , Pg.186 , Pg.187 , Pg.188 ]




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1.3- Dipolar cycloaddition reactions frontier molecular orbital theory

1.3- Dipolar cycloadditions frontier molecular orbital theory

1.3- dienes frontier orbitals of substituted

1.3- dipolar cycloaddition reactions dominant frontier orbitals

1.3- dipoles, frontier orbitals

21st Century Frontier Science

Acid-base concepts frontier orbitals

Acid-base reactions, frontier orbitals

Acrolein frontier orbitals

Alkenes frontier molecular orbital

Alkynes frontier orbitals

Allenes frontier orbitals

And the frontier orbital method

Anisole frontier orbitals

Aromatic compounds frontier orbitals

Azides frontier orbitals

Benzynes frontier orbitals

Beyond the Molecular Frontier: Challenges for

Butadiene frontier orbitals

Carbenes frontier orbital interactions

Carbonyl oxides frontier orbitals

Case Concerning the Frontier Dispute

Chemical frontier molecular orbital

Chemical reactivities frontier orbital theory

Conjugate addition frontier orbitals

Copyright © National Academy of Sciences. All rights reserved Frontiers in Chemical Engineering: Research Needs and Opportunities

Coupled with Computers Enables Exploration of New Frontiers

Crabgrass Frontier

Cycloaddition frontier Orbital description

Cycloaddition frontier-allowed pathway

Cycloaddition reactions frontier orbital interactions

Cycloaddition reactions frontier orbital theory

Cycloadditions frontier orbital description

Diazoalkanes frontier orbitals

Diazomethane frontier orbitals

Diels-Alder reaction frontier molecular

Diels-Alder reaction frontier orbitals

Diels-Alder reactions frontier orbital interactions

Diels-Alder reactions frontier-orbital method

Dienophiles frontier orbitals

Dipolar frontier orbital approach

Dipolarophiles frontier orbitals

Effective frontier

Effective frontier defined

Efficient frontier plot

Efficient frontier portfolio

Electrocyclic reactions Frontier Orbital analysis

Electron Densities and Frontier Orbital Energies

Electron density, frontier

Electron electrons, frontier

Electronic coupling frontier molecular orbital interactions

Electronic frontier molecular orbital energy

Electronic structure frontier orbitals

Electrophilic aromatic frontier orbital theory

Electrophilicity frontier orbitals

Energies of frontier orbitals

Enolate ions frontier orbitals

Exterior Frontier Orbital

Exterior Frontier Orbital Extension model

FMO (frontier molecular

FRONTIER CARBON CORP

FRONTIERS OF ORGANIC SUPERCONDUCTORS

Forbidden reactions formal frontier orbitals

Fragment concepts frontier orbitals

Frontier Configuration Theory of Spin Selection

Frontier Configurations and a New Classification of Annulenes

Frontier Controlled Chemical Reactivity

Frontier Dispute, Case Concerning

Frontier Electron Energy

Frontier MO theory

Frontier Molecular Orbital Approaches

Frontier Molecular Orbital Considerations

Frontier Molecular Orbital Theory radical reactions

Frontier Molecular Orbital theory, for Diels-Alder reactions

Frontier Molecular Orbitals (FMO)

Frontier Orbital Considerations

Frontier Orbital Interactions in the Transition States of One-Step -Cycloadditions

Frontier Orbital Interactions in the Transition States of One-Step 1,3-Dipolar Cycloadditions Sustmann Classification

Frontier Orbital and Charge Transfer Theories

Frontier Orbital of Collector and Oxygen

Frontier Orbital theory

Frontier Orbitals HOMO and LUMO

Frontier Orbitals Nguyen Trong Anh

Frontier Orbitals in Leapfrog Fullerenes

Frontier Research in Anesthesiology Confirms the Brain-Disabling Principle

Frontier analysis

Frontier atom, hybridization

Frontier band

Frontier band structure

Frontier bond characteristics

Frontier carbon atom

Frontier control

Frontier control reactivity

Frontier cyclohexanones

Frontier densities

Frontier electron population

Frontier electron theory

Frontier electrons

Frontier formation

Frontier fragment-orbital analysis

Frontier function

Frontier highest occupied molecular orbital

Frontier interactions

Frontier lowest unoccupied molecular orbital

Frontier model

Frontier molecular orbital

Frontier molecular orbital analysis

Frontier molecular orbital closing

Frontier molecular orbital energies

Frontier molecular orbital method

Frontier molecular orbital method (FMO electrocyclization

Frontier molecular orbital method (FMO photochemical electrocyclization

Frontier molecular orbital theor

Frontier molecular orbital theory

Frontier molecular orbital theory (FMO

Frontier molecular orbital theory chemical reactivity

Frontier molecular orbital theory cycloadditions

Frontier molecular orbital theory general reactivity

Frontier molecular orbital theory reactions

Frontier molecular orbital theory regioselectivity

Frontier molecular orbital theory relativity

Frontier molecular orbital theory synthesis

Frontier molecular orbital theory, redox

Frontier molecular orbitals

Frontier nitrogen atom

Frontier oibitals

Frontier orbital analysis

Frontier orbital analysis reactions

Frontier orbital approach

Frontier orbital approximation

Frontier orbital approximation HOMO-LUMO interactions

Frontier orbital approximation limitations

Frontier orbital calculations

Frontier orbital concept

Frontier orbital control

Frontier orbital correlation diagrams

Frontier orbital energies

Frontier orbital energies, definition

Frontier orbital interactions

Frontier orbital interactions between

Frontier orbital interactions between cation

Frontier orbital interactions in Diels—Alder

Frontier orbital interactions in Diels—Alder reaction

Frontier orbital method

Frontier orbital model

Frontier orbital positions

Frontier orbital positions HOMO)

Frontier orbital positions LUMO)

Frontier orbital scheme

Frontier orbital symmetries

Frontier orbital theory electron densities

Frontier orbital theory principle

Frontier orbital theory, pericyclic reactions

Frontier orbital, definition

Frontier orbital-controlled reaction

Frontier orbitals

Frontier orbitals (HOMO and

Frontier orbitals 1,3-dipolar cycloaddition

Frontier orbitals Fragment analysis

Frontier orbitals and Alder ene reaction

Frontier orbitals and acid-base reactions

Frontier orbitals and conjugate addition reactions

Frontier orbitals coefficients

Frontier orbitals defined

Frontier orbitals definition

Frontier orbitals dienes

Frontier orbitals effects

Frontier orbitals in electrocyclic reactions

Frontier orbitals in nucleophilic substitution

Frontier orbitals in photochemical cycloaddition

Frontier orbitals in radical chain reactions

Frontier orbitals in sigmatropic rearrangements

Frontier orbitals interactions

Frontier orbitals ketene

Frontier orbitals reacting with electrophiles

Frontier orbitals reacting with radicals

Frontier orbitals rules

Frontier orbitals, imine

Frontier second highest occupied molecular orbital

Frontier transition metal reactions

Frontier, efficient

Frontier-controlled interactions

Frontier-electron method

Frontier-orbital-controlled process

Frontiers in Chemical Engineering: Research

Frontiers in Chemical Engineering: Research Needs and Opportunities

Frontiers in Transition Metal-Containing Polymers, edited by Alaa S. Abd-El-Aziz and Ian Manners

Frontiers in nanotechnology-enabled orthopedic materials

Frontiers of Chemistry (Box

Frontiers of life

Hydrogen frontier molecular orbitals

Introduction frontier molecular orbital

Justice of the Right to Cross-Frontier Contacts

Ketenes frontier orbitals

Lead time frontier

Legitimacy of the Right to Cross-Frontier Contacts

Limitations and Exceptions of Frontier Orbital Theory

Main-group clusters frontier orbitals

Managing the lead-time frontier

Mass frontier

Materials research chemical engineering frontiers

Medecins Sans Frontieres

Molecular frontier

Molecular orbitals frontier orbital method

Molecular systems frontier orbital theory

New Frontiers in Asymmetric Catalysis, Edited by Koichi Mikami and Mark Lautens

New Frontiers in Epigenetic Modifications

New frontiers

Nitrile oxides frontier orbitals

Nitrile ylides frontier orbitals

Nitrones frontier orbitals

Nucleophilic addition frontier

Orbital interactions frontier molecular orbitals

Orbital, frontier

Orbitals frontier orbital symmetry

Organic Synthesis Challenging Natural Products and New Frontiers

Organic chemistry frontiers

Organometallic complexes frontier orbitals

Oxidation frontier molecular orbital

Ozone frontier orbitals

Pareto frontier

Pericyclic reaction frontier orbitals and

Pericyclic reactions frontier molecular orbital theory

Pericyclic reactions frontier orbitals

Pharmaciens Sans Frontieres

Phenyl azide frontier orbitals

Production possibilities frontier

Pyridinium cations frontier orbitals

Pyrrole frontier orbitals

Qualitative theories frontier molecular orbital theory

Radical chain reaction frontier orbital effects

Reactivity frontier orbital treatments

Research Frontiers

Sigmatropic reactions Frontier Orbital analysis

Sigmatropic rearrangements frontier orbital theory

Spectroscopic Support for Frontier Orbital Interactions

Supply chain management Frontier

Surface Frontier Molecular Orbitals

TATO-DMM AND INTERSUBSYSTEM FRONTIER

THE RESEARCH FRONTIER

The Frontier in Ionics Nonaqueous Solutions

The Frontiers of Photochemistry

The New Frontiers

The Next Frontier

The Right to Cross-Frontier Contacts

The Role of Frontier Orbitals

The Uses of Frontier Orbitals

The ancient art of winemaking meets frontier yeast science

The frontier orbital description of cycloadditions

Transition frontier orbitals theory

Transition state organic chemical reaction frontier

Two-Dimensional Nanostructures The Graphene Frontier

When Electrochemicals Were the Frontier

When Heavy Chemicals Were the Frontier

When High-Pressure and Catalytic Processes Became the Frontier

When Petroleum Refining Was the Frontier

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