The present invention relates to a group of novel electrochromic materials. More specifically, it relates to electrochromic materials based on either single or two-core viologen systems and the use of these viologen systems as a variable transmittance medium for the manufacture of an optical article, such as an ophthalmic lens.

The present invention relates to a group of novel electrochromic materials. More specifically, it relates to electrochromic materials based on either single or two-core viologen systems and the use of these viologen systems as a variable transmittance medium for the manufacture of an optical article, such as an ophthalmic lens.

Disclosed herein is a mixed-valence crystal superstructure assembled from a 2:1 host-guest inclusion complex. The complex comprises an aromatic guest encircled by two macrocycles, wherein the complex has an empirical charge greater than 0 and less than 1. Methods of preparing the compositions described herein are also disclosed.

Disclosed herein is a mixed-valence crystal superstructure assembled from a 2:1 host-guest inclusion complex. The complex comprises an aromatic guest encircled by two macrocycles, wherein the complex has an empirical charge greater than 0 and less than 1. Methods of preparing the compositions described herein are also disclosed.

A novel heterocyclic compound for an organic electroluminescent device excellent in long service life and light-emitting characteristics is provided. A cyclic azine compound has at least one substituent (substituent B) selected from a specific group.

A novel heterocyclic compound for an organic electroluminescent device excellent in long service life and light-emitting characteristics is provided. A cyclic azine compound has at least one substituent (substituent B) selected from a specific group.

Disclosed herein is a tricyclic octacationic cyclophane and complexes comprising the tricyclic octacationic cyclophane and a perylene diimide dye complexed therein and methods of using and making the cyclophane and complexes.

Disclosed herein is a tricyclic octacationic cyclophane and complexes comprising the tricyclic octacationic cyclophane and a perylene diimide dye complexed therein and methods of using and making the cyclophane and complexes.

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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