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Atomic bonds

The polarization fiinctions are essential in strained ring compounds because they provide the angular flexibility needed to direct the electron density mto the regions between the bonded atoms. [Pg.2172]

The energy required to break the bond between two covalently bonded atoms is called the bond dissociation energy . In polyatomic molecules this quantity varies with environment. For example, ammonia has three N—H bond dissociation energies ... [Pg.47]

This model (e.g., implemented in MMFF) allows the charges on each atom i to be modified by the electronegativity of the bonded atoms j. The additional charge q is normally zero, but it ensures that the correct total charge of a molecule or fragment is maintained. [Pg.345]

Quantum mechanical calculation of molecular dynamics trajectories can sim ulate bon d breakin g and frtrm ation.. Although you dt) n ot see th e appearance or disappearan ce ofhonds, you can plot the distan ce between two bonded atom s.. A distan ce excccdi n g a theoretical bond length suggests bond breaking. [Pg.90]

Note Restraints apply to distances, angles and dihedrals between bonded ornon bonded atoms. Yon can also restrain atoms to points in space. [Pg.105]

The forces between bonded atoms are very strong and considerable energy is required to cause a bond to deviate significantly from its equilibrium value. This is reflected in the magnitude of the force constants for bond stretching some typical values from the MM2 force field are shown in Table 4.1, where it can be seen that those bonds one would... [Pg.189]

Some force fields replace the Lennard-Jones 6-12 term between hydrogen-bonding atoms by ail explicit hydrogen-bonding term, which is often described using a 10-12 Lennard-Jones potential ... [Pg.233]

The Huckel method and is one of the earliest and simplest semiempirical methods. A Huckel calculation models only the 7t valence electrons in a planar conjugated hydrocarbon. A parameter is used to describe the interaction between bonded atoms. There are no second atom affects. Huckel calculations do reflect orbital symmetry and qualitatively predict orbital coefficients. Huckel calculations can give crude quantitative information or qualitative insight into conjugated compounds, but are seldom used today. The primary use of Huckel calculations now is as a class exercise because it is a calculation that can be done by hand. [Pg.33]

Organic molecules are generally composed of covalent bonded atoms with several well-defined hybridization states tending to have well-understood preferred geometries. This makes them an ideal case for molecular mechanics parameterization. Likewise, organic molecules are the ideal case for semiempirical parameterization. [Pg.283]

Left bonded atom linked to exocyclic iiitrogeni right bonded atom linked to ring N. TABLE VI-64. [Pg.278]

Left bonded atom linked to exocydic nitrogen right bonded atom linked to ring N. TABLE VI-69, R3 /R2 R, S- NCOR, R, = NRR. OR. SO R. ... [Pg.288]

The bond dipoles m Table 1 3 depend on the difference m electronegativity of the bonded atoms and on the bond distance The polarity of a C—H bond is relatively low substantially less than a C—O bond for example Don t lose sight of an even more important difference between a C—H bond and a C—O bond and that is the direction of the dipole moment In a C—H bond the electrons are drawn away from H toward C In a C—O bond electrons are drawn from C toward O As we 11 see m later chap ters the kinds of reactions that a substance undergoes can often be related to the size and direction of key bond dipoles... [Pg.17]

Formal charges are based on Lewis structures m which electrons are considered to be shared equally between covalently bonded atoms Actually polarization of N—H bonds m ammonium ion and of B—H bonds m borohydride leads to some transfer of positive and negative charge respectively to the hydrogens... [Pg.19]

Connect bonded atoms by a shared electron pair bond () represented by a dash (—)... [Pg.20]

Decoupling (Section 13 17) In NMR spectroscopy any process that destroys the coupling of nuclear spins between two nuclei Two types of decoupling are employed in NMR spectroscopy Broadband decoupling removes all the H- C couplings ojf resonance decoupling removes all H- C couplings except those between directly bonded atoms... [Pg.1280]

Heterogeneous reaction (Section 6 1) A reaction involving two or more substances present in different phases Hydro genation of alkenes is a heterogeneous reaction that takes place on the surface of an insoluble metal catalyst Heterolytic cleavage (Section 4 16) Dissociation of a two electron covalent bond in such a way that both electrons are retained by one of the initially bonded atoms Hexose (Section 25 4) A carbohydrate with six carbon atoms High density lipoprotein (HDL) (Section 26 11) A protein that carries cholesterol from the tissues to the liver where it is metabolized HDL is often called good cholesterol Histones (Section 28 9) Proteins that are associated with DNA in nucleosomes... [Pg.1285]

Homolytic cleavage (Section 4 16) Dissociation of a two electron covalent bond in such a way that one electron is re tamed by each of the initially bonded atoms... [Pg.1285]

For compounds containing only double-bonded atoms, the reference plane contains the double-bonded atoms and is perpendicular to the plane containing these atoms and those directly attached to them. It is customary to draw the formulas so that the reference plane is perpendicular to that of... [Pg.43]

Rule 3. When groups under consideration have double or triple bonds, the multiple-bonded atom is replaced conceptually by two or three single bonds to that same kind of atom. [Pg.45]


See other pages where Atomic bonds is mentioned: [Pg.146]    [Pg.217]    [Pg.591]    [Pg.2824]    [Pg.119]    [Pg.349]    [Pg.126]    [Pg.154]    [Pg.361]    [Pg.191]    [Pg.210]    [Pg.211]    [Pg.101]    [Pg.101]    [Pg.184]    [Pg.194]    [Pg.211]    [Pg.212]    [Pg.479]    [Pg.486]    [Pg.126]    [Pg.270]    [Pg.28]    [Pg.1291]    [Pg.210]    [Pg.211]   
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Abstraction, hydrogen atom, from O—H bonds

Abstraction, hydrogen atom, from bonds

Addition of bromine atoms to double and triple bonds

Addition of carbon atoms to double and triple bonds

Addition of chlorine atoms to double and triple bonds

Addition of fluorine atoms to double and triple bonds

Addition of iodine atoms to double and triple bonds

Addition of nitrogen atoms to double and triple bonds

Addition of oxygen atoms to double and triple bonds

Addition of selenium atoms to double and triple bonds

Addition of sulphur atoms to double and triple bonds

Addition of tellurium atoms to double and triple bonds

Agostic Bonding and Hydrogen Atom Migrations

Alkanes Hydrocarbons containing only single bonds between carbon atoms

Alternating polarity of atoms in valence bond structures

An atomic property expressed as a sum of bond contributions

Aromaticity bond orbital atomic charges

Atom bond coordinate covalent

Atom bond multiple

Atom bonding

Atom bonding

Atom covalent bond

Atom electrovalent bonding

Atom transfer radical polymerization carbon—halogen bond

Atom-Bond Electronegativity Equalization

Atom-Bond Electronegativity Equalization Method

Atomic Bond Separation Mechanisms

Atomic Charges, Bond Properties, and Molecular Energies, by Sandor Fliszar

Atomic Structure and Interatomic Bonding

Atomic Structure and Polymer Chain Bonds

Atomic Structure, Radiochemistry and Chemical Bonding

Atomic and bond dipoles

Atomic bond distances, optimized

Atomic bonding

Atomic bonding

Atomic bonding energy, 43 (Table

Atomic bonding forces

Atomic bonding secondary

Atomic bonds Applications

Atomic bonds Boehmite

Atomic bonds Calcium aluminate

Atomic bonds Cements

Atomic bonds Classifications

Atomic bonds Clays

Atomic bonds Coesite

Atomic bonds Concrete

Atomic bonds Deposits

Atomic bonds Evaluation

Atomic bonds Forming

Atomic bonds Glasses

Atomic bonds History

Atomic bonds Phase diagram

Atomic bonds Processing

Atomic bonds Production

Atomic bonds Structures

Atomic distance bond-length, lattice constant

Atomic hybrids and bonding geometry

Atomic orbital bonding states

Atomic orbital chemical bonds

Atomic orbital combinations giving rise to bonding molecular orbitals for methane

Atomic orbitals bonding between

Atomic orbitals bonding molecular orbital

Atomic orbitals chemical bonding

Atomic orbitals valence bond theory

Atomic orbitals, bond formation with

Atomic orbitals, combining bonding

Atomic overlap matrices, bond orders

Atomic properties chemical bonds and

Atomic radius/radii bonding

Atomic structure and bonding

Atomic structure chemical bonds

Atomic-Level Bond Breaking

Atomic-interaction-based theory chemical bonding

Atoms and bonds

Atoms bonding interactions between

Atoms bonding sites

Atoms bonding within polyatomic ions

Atoms bonds

Atoms bonds

Atoms chemical bond strengths

Atoms chemical bonds

Atoms chemical bonds and

Atoms in a Molecule Are Held Together by Chemical Bonds

Atoms pi bond between two, with one atom

Atoms spring-like bond

Atoms, bonded pairs

BONDS BETWEEN ATOMS

BONDS BETWEEN ATOMS induced

Bond Dissociation Energy. Atomization Enthalpy

Bond Formation Using Atomic Orbitals

Bond Orbitals for Atoms Carrying Unshared Electron Pairs

Bond Order in SHMO Theory (Sab 0, One Orbital per Atom)

Bond The force that holds two atoms

Bond The force that holds two atoms together

Bond Type and Atomic Arrangement

Bond dissociation enthalpies atomization

Bond enthalpies atomization

Bond metal atomic orbitals, quadruple

Bond strength variation with atomic

Bond-atom polarizability

Bonded atoms

Bonded atoms definition

Bonding II Molecular Geometry and Hybridization of Atomic Orbitals

Bonding and Atomic Spacing

Bonding aspects From atoms to solid state

Bonding atomic properties

Bonding atomic radius

Bonding atomic radius (covalent

Bonding between carbon atoms

Bonding between chromium atoms

Bonding between metal atoms and organic

Bonding between metal atoms and organic pi systems

Bonding between unlike atoms

Bonding halogen atom

Bonding heavier ligand atoms

Bonding in Atoms with Multiple Connectivity

Bonds between In and Group VI Atoms

Bonds between atoms and molecules

Bonds between different atoms

Bonds in atoms

Bonds unlike atoms

Bonds with Atoms Containing Unshared Electrons

Boranes with Two Boron-Bonded Nitrogen Atoms

Broken-atomic-bond model

By Formation of Three Bonds from Atom Fragments

By Formation of Two Bonds from Atom Fragments

C-H Bonds Adjacent to a Nitrogen Atom

Carbon atom in bond-line drawings

Carbon atom, bonding

Carbon atom, covalent bond with

Carbon atoms bonding characteristics

Carbon atoms covalent bonding ability

Carbon atoms ionic bond formation

Carbon atoms single/double bonds, alternation between

Carbon atoms, bonding nature

Central atom concepts valence bond theory

Chemical Bonding II Molecular Geometry and Hybridization of Atomic Orbitals

Chemical Bonds The Formation of Compounds from Atoms

Chemical bonding atomic orbital overlap

Chemical bonding atomic-number dependence

Chemical bonding central atom

Chemical bonding of atomic adsorbates

Chemical bonding terminal atom

Chemical bonding third atomic orbital

Complexes with P Units Bonded to M Atoms

Coordinate covalent bonds nitrogen atom

Coplanar atoms, partial double-bond

Covalent Bonds Between Adjacent Atoms

Covalent bonds network atomic solid

Crystal atomic distance, bond-length

Definition of Templates (Polygons, Benzene, Bond, Atom, etc

Dianhydro Sugars Not Involving the Anomeric Carbon Atom in Anhydro Bonds

Distribution of Atom Types H-bond Donors and Acceptors

Double atoms 421 bond conjugated) layer

Double bond Effective atomic number

Double bond additions carbon atom-alkene reactivity

Double bond additions carbon atom-aromatic compound reactivity

Double bonds atoms

Double bonds chiral carbon atoms

Double bonds linked by C and N atoms

Double bonds linked by C and P atoms

Double bonds linked by C and Si, Ge or Sn atoms

Double: bonds, 180 decomposition atoms

Effective Bond Charges from Rotation-Free Atomic Polar Tensors

Effective Induced Bond Charges From Atomic Polarizability Tensors

Effects in Atoms with Consequences for Chemical Bonding

Energy of atomic bonds

Ethylene, atomic orbital model localized bonds

Factors that Influence the Electronic Nature of Bonds and Atoms

Fluorine atoms, chemical bonds

Formation of Exopolyhedral a Bonds between Cage Boron Atoms and Transition Elements

Formation of Two Bonds Atom Fragment by Cycloaddition

Formation of Two Bonds Atom Fragment by Other Processes

Formation of Two Bonds Four-Atom Fragment and Sulfur

Formulation Atomic Valence and Bond Geometry

Formulation Bond and Atomic Valence

Four-bonded atoms

Geometry around Bonded Carbon Atoms

Halides and Halogen Atoms as Hydrogen-Bond Acceptors

Heavy atom bonds

Heavy atom tunneling, hydrogen bonds

Heterolytic Fission of Bonds Attached to a Vinyl Carbon Atom

Hydrogen Atom Abstraction from a Bonded Carbon Ligands

Hydrogen Bonds Involving Fluorine Atoms

Hydrogen atom abstraction from 0-H bonds

Hydrogen atom bonding interactions

Hydrogen atom transfer bond dissociation energies

Hydrogen atoms, bond formation

Hydrogen atoms, bond formation between

Hydrogen bond electronegative atom

Hydrogen bond fluorine atom

Hydrogen bond nitrogen atom

Hydrogen bond oxygen atom

Hydrogen bond types chain atoms

Hydrogen bonding atoms

Hydrogen bonds between oxygen atoms

Hydrogen bonds involving transition metal atoms

Hypercoordinate Bonding to First-row Atoms

Inter-Atomic Vibration, Interaction, and Bonding Localization

Intermolecular forces bonding between atoms

Intramolecular forces bonding between atoms

Iodine bonding atomic radius

Metal atomic bond lengths

Metal atoms with carbon-halogen bonds

Metal atoms, bonding between organic

Molecular descriptor hydrogen-bonding donor atoms

Monovalent atom bond exchange

Network atomic solids bonds

Nitrogen atom, bonding

Nucleophilic Displacements on Singly Bonded Carbon Atoms

OH-bonds, hydrogen atom abstraction from

Orbitals, atomic bonding

Orbitals, atomic multiple bonds

Oxygen Bonded to Activated Tetrahedral Carbon Atoms

Oxygen Bonded to Trigonal Carbon Atoms

Oxygen atom transfer peroxo bond

Oxygen atom, bonding

O—H bonds, hydrogen atom abstraction

Phosphorus—oxygen bonds atomic hydrogen

Pi bond between two atoms

Polar Bond, Effective Charges of Atoms

Properties of Atoms, Radicals, and Bonds

Quadruple Bonds between Transition Metal Atoms

Quadruple bonds between metal atoms

Reaction carbon atom bonding with

Reaction with Free Radicals Hydrogen Atom Abstraction and One- or Three-Electron Bonding

Reactions of Carbosilanes Containing Side Chains Bonded to Si-Atoms in the Molecular Skeleton

Reactions without Metal-Ligand Atom Bond Cleavage

Restricted Rotation about Single Bonds between Atoms with Unshared Electron Pairs

Sets of Atoms Differing in Mass or Chemical Bond Strength

Siloxane Oligomers with Functional Groups Directly Bonded to the Terminal Silicon Atoms (Si—X)

Structural descriptors hydrogen-bonding donor atoms

Sure That Each Carbon Atom Has Four Bonds

Symmetrical Hydrogen Bonds between Oxygen Atoms

THE ATOMIC BONDING OF CARBIDES

Tetrahedrally bonded carbon atoms

The Atomic Bond

The Chemical Bond Formation Energy Based on Rigid Atomic Orbitals

The Ionic Bond Transfer of Electrons from One Atom to Another

The Oxygen of an Ether Croup Is Bonded to Two Carbon Atoms

The atomic sizes and bonding radii of main group elements

Three-bonded atoms

Three-centre bonds atomic properties

Topological Definition of Atoms, Bonds, and Structure

Topological atom bonding description

Two complexes containing dative and covalent bond distances between identical atom pairs

Types of bonds formed by the carbon atom

Unstable compounds with double-bonded silicon and germanium atoms (silenes, silanones, germanones, germathiones)

Valence bond theory hybridization of atomic orbitals

Valence-Bond Structures and Quinquevalent Nitrogen Atoms

What orbitals are involved in multiple bond formation between atoms

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