A novel organometallic complex having high heat resistance is provided. The organometallic complex, which includes a structure represented by General Formula (G1), includes iridium and a ligand. The ligand has a pyrazine skeleton. Iridium is bonded to nitrogen at the 1-position of the pyrazine skeleton. A phenyl group that has an alkyl group as a substituent is bonded at each of the 2- and 3-positions of the pyrazine skeleton, and a phenyl group that has a cyano group as a substituent is bonded at the 5-position of the pyrazine skeleton. The ortho position of the phenyl group bonded at the 2-position of the pyrazine skeleton is bonded to iridium.

##STR00001##

In the formula, each of A.sup.1 to A.sup.4 independently represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms. Each of R.sup.1 to R.sup.6 independently represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. Each of R.sup.7 to R.sup.11 independently represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms, and a cyano group. At least one of R.sup.7 to R.sup.11 represents a cyano group.

An organometallic compound may be represented by one selected from the group of Formulae 5 to 8: ##STR00001##

A novel organometallic complex having high heat resistance is provided. The organometallic complex, which includes a structure represented by General Formula (G1), includes iridium and a ligand. The ligand has a pyrazine skeleton. Iridium is bonded to nitrogen at the 1-position of the pyrazine skeleton. A phenyl group that has an alkyl group as a substituent is bonded at each of the 2- and 3-positions of the pyrazine skeleton, and a phenyl group that has a cyano group as a substituent is bonded at the 5-position of the pyrazine skeleton. The ortho position of the phenyl group bonded at the 2-position of the pyrazine skeleton is bonded to iridium. ##STR00001## In the formula, each of A.sup.1 to A.sup.4 independently represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms. Each of R.sup.1 to R.sup.6 independently represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. Each of R.sup.7 to R.sup.11 independently represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms, and a cyano group. At least one of R.sup.7 to R.sup.11 represents a cyano group.

Provided are compounds having a ligand L.sub.A of Formula I ##STR00001##
that are useful as emissive compounds in organic light emitting devices.

The present invention relates to metal complexes and to electronic devices, especially organic electroluminescent devices, comprising these metal complexes, especially as emitters.

The synthesis, structure, and reactivity of a family of iridium-based molecular cluster complexes, including neutron and X-ray single-crystal diffraction measurements, are provided. It is found that one complex, which includes an Ir.sub.3H.sub.6(.sup.3H) trinuclear core, exhibits reactivity for reversible CO.sub.2 hydrogenation via hydride transfer. This reactivity is unlike previous reports of one known Ir.sub.3H.sub.6(.sup.3H) complex, which is inert.

A novel organometallic complex having high heat resistance is provided. The organometallic complex, which includes a structure represented by General Formula (G1), includes iridium and a ligand. The ligand has a pyrazine skeleton. Iridium is bonded to nitrogen at the 1-position of the pyrazine skeleton. A phenyl group that has an alkyl group as a substituent is bonded at each of the 2- and 3-positions of the pyrazine skeleton, and a phenyl group that has a cyano group as a substituent is bonded at the 5-position of the pyrazine skeleton. The ortho position of the phenyl group bonded at the 2-position of the pyrazine skeleton is bonded to iridium.

##STR00001##

In the formula, each of A.sup.1 to A.sup.4 independently represents a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms. Each of R.sup.1 to R.sup.6 independently represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms. Each of R.sup.7 to R.sup.11 independently represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 12 carbon atoms, and a cyano group. At least one of R.sup.7 to R.sup.11 represents a cyano group.

A novel organometallic complex with high reliability is provided. A light-emitting element includes an EL layer between a pair of electrodes. The EL layer includes at least a light-emitting layer. The light-emitting layer contains an organometallic complex. The organometallic complex includes a first ligand and a second ligand which are coordinated to a central metal. The HOMO is distributed over the first ligand, and the LUMO is distributed over the second ligand. The first ligand and the second ligand are cyclometalated ligands.

Particles of an organic acid salt of an amino acid amide or ester local anesthetic are employed as agents for the improved alleviation of pain. Particularly, the particles find use with surgically created wounds, where the particles may be administered directly into the bed of the wound or topically for transdermal transport.

Methods for deposition of elemental metal films on surfaces using metal coordination complexes comprising nitrogen-containing ligands are provided. Also provided are nitrogen-containing ligands useful in the methods of the invention and metal coordination complexes comprising these ligands.