Lithium atom Lithium atom A lithium atom is an atom of the chemical element lithium. Lithium is composed of three electrons bound by the electromagnetic force to a nucleus containing three protons along with either three or four neutrons, depending on the isotope, held together by the strong force. Similarly to the case of the helium atom, a closed-form solution to the Schrödinger equation for the lithium atom has not been found. However, various approximations, such as the Hartree–Fock method, can be used to estimate the ground state energy and wavefunction of the atom. The quantum defect is a value that describes
Atom economy yield, because a high-yielding process can still result in substantial byproducts. Examples include the Cannizzaro reaction, in which approximately 50% of the reactant aldehyde becomes the other oxidation state of the target; the Wittig reaction, which uses high-mass phosphorus reagents that ultimately become waste; and the Gabriel synthesis, which produces a stoichiometric quantity of phthalic acid If the desired product has an enantiomer the reaction needs to be sufficiently stereoselective even when atom economy is 100%. A Diels-Alder reaction is an example of a potentially very atom efficient reaction that also can be chemo-, regio-, diastereo- and enantioselective. Catalytic hydrogenation