Ions {complex ion} can have more than one atom. Complex ions typically have central positive atom {mononuclear atom}. Mononuclear atom binds to negative atom ligands. Ligands can chelate to central atom at two or more sites.
properties
Central atom can have high charge, small radius, and filled or half-filled d orbitals. Central atom can have low charge, large radius, and odd number of d-orbital electrons. If central atom has higher positive charge, greater atomic weight, and/or more electrons in d orbitals, complex ion is more stable. d orbitals are most stable when they are half full or have 3, 6, or 8 electrons.
types
Heme has iron as central atom. Chlorophyll has magnesium as central atom. Vitamin B12 has cobalt as central atom.
In covalent compounds, ionization potential is inversely proportional to half the distance {effective atomic radius} between two covalently bound nuclei. Effective atomic radius ranges from 0.037 nanometers to 0.3 nanometers.
In gases, atoms have potential energies, which range from -0.9 eV to +3.6 eV, to attract additional electrons {electron affinity}. Atom electronegativity directly correlates with electron affinity.
Atomic nuclei attract electrons in shared orbitals {electronegativity}. Electronegativity is proportional to sum of ionization potential and electron affinity.
energy
For two bonded atoms, electronegativity difference is proportional to square root of bond-energy ionic bonding part {partial ionic character}, which ranges from 0.8 eV to 4.0 eV.
bonds
If both atoms have high electronegativity, they have covalent bonding. If both atoms have low electronegativity, they have metallic bonding. If one atom has high electronegativity and one atom has low electronegativity, they have ionic bonding.
location
Atom with higher electronegativity has higher probability of containing bonding electrons, and lower probability of containing antibonding electrons, than other atom.
To remove outermost electron, gas atoms require energy {ionization potential} {ionization energy}, which ranges from 4 eV to 24 eV.
Dots can represent electrons in molecule electron structures {Lewis structure}. Atoms, except hydrogen with two dots, have eight dots, to represent electrons in outer shell. Two dots are at atom right, bottom, left, or top. If two atoms bond, two dots are between them. If two atoms have double bond, four dots are between them.
Molecules {radical, molecule}| {free radical} can have no charge but have only one unpaired electron in outer orbital. Peroxides have oxygen free radicals. When peroxide or double-bonded carbon binds to carbon, carbon atom can have free radical.
Two non-metal-atom electrons {unshared pair} can be in non-bonding outer-shell orbital.
Atoms have number {valence, atom}| of outer-shell electrons, or missing outer-shell electrons, needed to complete outer shell.
5-Chemistry-Inorganic-Chemical-Molecule
Outline of Knowledge Database Home Page
Description of Outline of Knowledge Database
Date Modified: 2022.0225