"A chemical bond is a lasting attraction between atoms or ions that enables the formation of molecules, crystals, and other structures."
Basic principles of chemical bonding in drug development, concepts of molecular and electronic properties of drugs, computational chemistry in drug discovery.
Valence electrons: Electrons located in the outermost shell of an atom which are involved in chemical bonding.
Lewis structures: Structural diagrams that show the arrangement of atoms and electrons in a molecule.
Ionic bonding: A type of chemical bonding where two oppositely charged ions are held together by electrostatic forces.
Covalent bonding: A type of chemical bonding where atoms share electrons to form a stable molecule.
Polar covalent bonding: A type of covalent bonding where atoms share electrons unevenly resulting in a partial positive and negative charge on the molecule.
Nonpolar covalent bonding: A type of covalent bonding where electrons are shared equally resulting in no partial charges on the molecule.
Hydrogen bonding: A type of intermolecular bonding where a hydrogen atom is attracted to a highly electronegative atom such as oxygen or nitrogen.
Dipole-dipole interactions: Intermolecular forces where polar molecules are attracted to each other based on the partial charges present.
London dispersion forces: Intermolecular forces where nonpolar molecules are attracted to each other due to the temporary, random fluctuations in electron distribution.
VSEPR theory: A model used to predict the shape of a molecule based on the repulsion between electron pairs in the outermost shell of an atom.
Molecular polarity: A measure of how evenly distributed the electrons are in a molecule, which determines how attracted it is to other polar molecules.
Resonance structures: Alternative Lewis structures that show the different ways a molecule can be arranged with the same bonding and valence electron distribution.
Hybridization: The mixing of atomic orbitals to form a new set of hybrid orbitals that are involved in covalent bonding.
Intermolecular forces: Forces of attraction or repulsion between molecules that determine their physical properties.
Chemical reactions: The process of breaking and forming chemical bonds to create a new chemical compound.
Ionic Bonding: This type of bonding occurs between oppositely charged ions, resulting in a transfer of electrons from one atom to another.
Covalent Bonding: This type of bonding occurs when two or more atoms share electrons in order to achieve a stable octet of valence electrons.
Hydrogen Bonding: This type of bonding occurs between a hydrogen atom, covalently bonded to one molecule, and an electronegative atom (such as oxygen or nitrogen) in a neighboring molecule.
Van der Waals Forces: This is a weak, non-covalent interaction between molecules that arises from fluctuations in the electron density of the molecules.
Dipole-Dipole Interactions: This interaction occurs between polar molecules, with the partial negative charge of one molecule attracted to the partial positive charge of another.
London Dispersion Forces: This is the weakest of the intermolecular forces and arises from instantaneous dipoles that occur in non-polar molecules.
Metallic Bonding: This type of bonding occurs between metal atoms, where the valence electrons are delocalized, allowing for a strong bonding network between the metal atoms.
Steric Effects: This refers to the effect that the spatial arrangement (or shape) of molecules has on their reactivity, solubility, and other properties.
Hydrophobic Effects: This refers to the tendency of non-polar molecules to aggregate together in aqueous environments, due to the unfavorable interaction between the hydrophobic molecules and water.
Ion-Dipole Interactions: This interaction occurs between an ion and a polar molecule, with the positively or negatively charged ion attracting the partial negative or positive charge of the polar molecule.
Pi-Pi Interactions: This interaction occurs between aromatic rings, resulting in a stacking of the rings in a specific arrangement.
Pi-Cation Interactions: This interaction occurs between a cation (positively charged ion) and an aromatic ring, with the delocalized electrons of the ring interacting with the cation.
Electrostatic Interactions: This refers to the interaction between charged entities, such as an ion and a charged molecule.
Stereoelectronic Effects: This refers to the effect that the electronic structure of a molecule has on its reactivity and properties, based on the three-dimensional arrangement of its atoms.
Chirality: This refers to the fact that many molecules have a non-superimposable mirror image, resulting in different biological activities and properties.
"The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds."
"The bond may result from...the sharing of electrons as in covalent bonds."
"There are 'strong bonds' or 'primary bonds' such as covalent, ionic and metallic bonds."
"There are 'weak bonds' or 'secondary bonds' such as dipole-dipole interactions, the London dispersion force, and hydrogen bonding."
"The negatively charged electrons surrounding the nucleus and the positively charged protons within a nucleus attract each other."
"Electrons shared between two nuclei will be attracted to both of them."
"Constructive quantum mechanical wavefunction interference stabilizes the paired nuclei."
"Bonded nuclei maintain an optimal distance (the bond distance) balancing attractive and repulsive effects explained quantitatively by quantum theory."
"The atoms in molecules, crystals, metals, and other forms of matter are held together by chemical bonds."
"All bonds can be described by quantum theory, but, in practice, simplified rules and other theories allow chemists to predict the strength, directionality, and polarity of bonds."
"The octet rule and VSEPR theory are examples."
"More sophisticated theories are valence bond theory, which includes orbital hybridization and resonance."
"More sophisticated theories...include molecular orbital theory, which includes the linear combination of atomic orbitals and ligand field theory."
"Electrostatics are used to describe bond polarities and the effects they have on chemical substances."
"The strength of chemical bonds varies considerably."
"The octet rule is an example [of a theory] that allows chemists to predict the strength, directionality, and polarity of bonds."
"The VSEPR theory is an example [of a theory] that allows chemists to predict the strength, directionality, and polarity of bonds."
"Orbital hybridization is a component of valence bond theory."
"Ligand field theory is a component of molecular orbital theory."