Embodiments of the present disclosure relate generally to novel achiral and chiral sulfur-, nitrogen- and phosphorus-containing ligands, designated as NNS-type, P(O)NS-type, PNS-type, SNNS-type, SNNP(O)-type, or SNNP-type polydentate ligands and transition metal complexes of these ligands, including iridium complexes having PNS-type and NNS-type ligands. The catalysts derived from these ligands and transition metal complexes may be used in a wide range of catalytic reactions, including hydrogenation and transfer hydrogenation of unsaturated organic compounds, dehydrogenation of alcohols and boranes, various dehydrogenative couplings, chemoselective hydrogenation of ,-unsaturated alcohols, and other catalytic transformations.

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.

An organometallic compound represented by Formula 1:

##STR00001## wherein, in Formula 1, groups and variables are the same as described in the specification.

Provided is a catalyst for producing hydrogen, which catalyst has higher performance than conventional catalysts since, for example, it exhibits a certain high level of activity in an aqueous formic acid solution at high concentration even without addition of a solvent, amine and/or the like. The metal phosphine complex is a metal phosphine complex represented by General Formula (1): MH.sub.m(CO)L.sub.n, wherein M represents an iridium, iron, rhodium or ruthenium atom; in cases where M is an iridium or rhodium atom, m=3 and n=2, and in cases where M is an iron or ruthenium atom, m=2 and n=3; and the number n of Ls each independently represent a tri-substituted phosphine represented by General Formula (2): PR.sup.1R.sup.2R.sup.3. The catalyst for producing hydrogen comprises the metal phosphine complex as a constituent component.

A composition that contains an iridium complex and an isomer of the iridium complex, in which the amount of the isomer of the iridium complex is decreased. The iridium complex is a homo-N-trans (HNT) iridium complex having an iridium atom, and a first ligand, a second ligand, and a third ligand that are bonded to the iridium atom. The isomer has an iridium atom, a fourth ligand, a fifth ligand, and the third ligand. The composition ratio of the isomer relative to a total of the iridium complex and the isomer is 1.0% or less.

A method for manufacturing 2-dimensional dimethylglyoxime-iridium (DMG-Ir) nanosheet is used to manufacturing the 2-dimensional DMG-Ir nanosheet which can quickly react with a nickel (Ni.sup.2+) ion and form a coordination complex in crimson red. By the use of the manufactured 2-dimensional DMG-Ir nanosheet, the problem of poor reactivity of the conventional method for detecting the Ni.sup.2+ ion using DMG can be solved. The method for manufacturing 2-dimensional DMG-Ir nanosheet includes promoting the reaction between iridium (Ir) salt and DMG in a basic environment. Preferably, the promotion of the reaction between the Ir salt and DMG includes dissolving the Ir salt and DMG in an alkaline aqueous solution to form a mixture. The mixture is probe sonicated for a predetermined time with a pulse on time and a pulse off time, and a hydrothermal reaction is further carried out to the resulted mixture. The 2-dimensional DMG-Ir nanosheet manufactured by the method and a colorimetric system are also disclosed.

A compound having a first ligand L.sub.A with a structure of Formula I,

##STR00001##

where two consecutive ones of X.sup.1 to X.sup.8 are C and are joined to a structure of Formula II,

##STR00002##

is provided. In Formula I, moiety A is a monocyclic ring or a polycyclic fused ring system; each of Z.sup.1 to Z.sup.2 and X.sup.1 to X.sup.12 is C or N; each of Y.sup.1 and Y.sup.2 is a linker; K is a direct bond or a linker; each substituent is hydrogen or a General Substituent defined herein; and L.sub.A is coordinated to a metal M. Also provided is a compound having a formula Ir(L.sub.A*).sub.x(L.sub.B*).sub.y(L.sub.C*).sub.z as defined herein. Formulations, OLEDs, and consumer products containing these compounds are further provided.

A compound including a first ligand L.sub.A of Formula I,

##STR00001##

is provided. In Formula I, moiety B is a fused polycyclic ring system; X.sup.1 to X.sup.4 are each C or N; K is a direct bond or a linker; L.sub.A is coordinated to a metal. Formulations, OLEDs, and consumer products containing such compounds are also provided.