Publisher Summary This review is concerned with the neglected class of inorganic compounds, which contain ions of the same element in two different formal states of oxidation. Although the number of references cited in our review show that many individual examples of this class have been studied, yet they have very rarely been treated as a class, and there has never before, to our knowledge, been a systematic attempt to classify their properties in terms of their electronic and molecular structures. In the past, systems containing an element in two different states of oxidation have gone by various names, the terms “mixed valence,” nonintegral valence,” “mixed oxidation,” “oscillating valency,” and “controlled valency” being used interchangeably. Actually, none of these is completely accurate or all-embracing, but in our hope to avoid the introduction of yet another definition, we have somewhat arbitrarily adopted the phrase “mixed valence” for the description of these systems. The concept of resonance among various valence bond structures is one of the cornerstones of modern organic chemistry.

Mixed Valence Chemistry-A Survey and Classification

Oxidations carried out by means of vanadium oxide catalysts

The layered oxides of vanadium and molybdenum have been studied for close to 40 years as possible cathode materials for lithium batteries or electrochromic systems. The highly distorted metal octahedra naturally lead to the formation of a wide range of layer structures, which can intercalate lithium levels exceeding 300 Ah/kg. They have found continuing success in medical devices, such as pacemakers, but many challenges remain in their application in long-lived rechargeable devices. Their high-energy storage capability remains an encouragement to researchers to resolve the stability concerns of vanadium dissolution and the tendency of lithium and vanadium to mix changing the crystal structure on cycling the lithium in and out. Nanomorphologies have enabled higher reactivities to be obtained for both vanadium and molybdenum oxides, and with the latter show promise for electrochromic displays.

Layered vanadium and molybdenum oxides: batteries and electrochromics

Within the framework of a program aiming to improve the existing extractive recovery technology of fermentation products, the state of the art is critically reviewed. The acids under consideration are propionic, lactic, pyruvic, succinic, fumaric, maleic, malic, itaconic, tartaric, citric, and isocitric, all obtained by the aerobic fermentation of glucose via the glycolytic pathway and glyoxylate bypass. With no exception, it is the undissociated monomeric acid that is extracted into carbon-bonded and phosphorus-bonded oxygen donor extractants. In the organic phase, the acids are usually dimerized. The extractive transfer process obeys the Nernst law, and the measured partition coefficients range from about 0.003 for aliphatic hydrocarbons to about 2 to 3 for aliphatic alcohols and ketones to about 10 or more for organophosphates. Equally high distribution ratios are measured when long-chain tertiary amines are employed as extractants, forming bulky salts preferentially soluble in the organic phase.

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/bit.22375

Extraction chemistry of fermentation product carboxylic acids

The Bond-Valence Method: An Empirical Approach to Chemical Structure and Bonding

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Vanadium Pentoxide - a Compound with Five-Coordinated Vanadium Atoms.

/pdf/a-refinement-of-the-crystal-structure-of-v6o13-37fku1m987.pdf

A Refinement of the Crystal Structure of V6O13.

/pdf/the-distribution-of-organic-compounds-between-iso-butanol-3szmez1grj.pdf

The Distribution of Organic Compounds Between iso-Butanol and Water.

/pdf/the-crystal-structure-of-nh4-2cr2o7-with-a-discussion-of-the-2f9xlbvuw4.pdf

The Crystal Structure of (NH4)2Cr2O7. With a Discussion of the Relation between Bond Number and Interatomic Distances.

/pdf/on-the-crystal-structure-of-a-new-vanadium-oxide-v4-o9-3ukj7ct91w.pdf

Karl-Axel Wilhelmi

Papers

Vanadium Pentoxide - a Compound with Five-Coordinated Vanadium Atoms.

A Refinement of the Crystal Structure of V6O13.

The Distribution of Organic Compounds Between iso-Butanol and Water.

The Crystal Structure of (NH4)2Cr2O7. With a Discussion of the Relation between Bond Number and Interatomic Distances.

On the crystal structure of a new vanadium oxide, V4 O9