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8. Alan G. MacDiarmid - Bibliography from ALAN GRAHAM MACDIARMID. 14 April 1927 — 7 February 2007

Author

Holmes, Andrew B., Klein, Michael L., and Baughman, Ray H.

Abstract

Alan G. MacDiarmid was an inorganic chemist by training who pioneered the field of synthetic metals. He grew up in a family that lived frugally, and he had to work in the Chemistry Department of the Victoria University of Wellington as a laboratory assistant before he could undertake part-time degree studies. He was awarded a Fulbright Scholarship to the University of Wisconsin, where he completed his first PhD with Norris Hall. The desire to receive a higher degree in the UK led to a Shell Scholarship to complete a second doctorate with Harry Emeléus FRS. After a sojourn at the University of St Andrews, Alan MacDiarmid was appointed to an academic position at the University of Pennsylvania, where he remained essentially for his whole career. His early research was based on the properties of silicon hydrides, but he also became interested in poly(sulfur nitride). This led to a search in collaboration with Alan J. Heeger for intrinsically conducting non-metallic materials. A chance meeting with Hideki Shirakawa at the University of Tokyo led to MacDiarmid being shown thin metallic-like films of poly(acetylene) made in Shirakawa's laboratory. Shirakawa travelled to Philadelphia to collaborate with MacDiarmid and Heeger on the halogen ‘doping’ of poly(acetylene), which led to the discovery that the doped material was an excellent conductor. Thus, the field of synthetic metals was born. This paradigm-shifting work in which a polymer was shown to be a conductor led to the award of the 2000 Nobel Prize in Chemistry to these three individuals. MacDiarmid went on to study in great detail the properties of polyaniline; the fact that it could be processed from solution and further modified by oxidative and protonic doping led to all sorts of potentially interesting opportunities in optoelectronics. From all this research, the modern field of organic electronic materials emerged as an important disruptive technology whose advancement depended on an entirely new branch of interdisciplinary science.

Published
2023
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22. Tunable production of elemental Se vs.H2Se through photocatalytic reduction of selenate in synthetic mine impacted brine: engineering a recoverable Se productElectronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d2ew00553k

Author

Holmes, Andrew B., Ngan, Aldrich, Giesinger, Kayleanna, and Gu, Frank

Abstract

In this paper, we investigate the tunability of Se reduction products (Se0(s)vs.H2Se(g)) during the photocatalytic reduction of selenate over TiO2, using formic acid as an electron hole scavenger, in synthetic mine-impacted brines (SMIB). Photocatalytic reduction can effectively remove Se from SMIB to <2 μg L−1from an initial Se concentration of >3300 μg L−1in under 10 × 1019photons cm−2. An increase in solution temperature led to a marked increase in selenate removal kinetics and an increase in selectivity towards H2Se(g), while increasing the concentration of formic acid led to an increase in selenate removal kinetics and a decrease in the selectivity towards H2Se(g). A bivariate response surface analysis was used to elucidate the mechanism behind the production of >99% gaseous H2Se or >85% solid Se0, under varying reaction conditions. Finally, a two-pronged electron transfer model is proposed to explain the selectivity towards Se0(s)vs.H2Se(g)under varying conditions: (i) Se0(s)is produced through direct reduction of selenate by TiO2conduction band electrons and (ii) H2Se gas is produced through electrons transferred into Se0, followed by an autocatalytic reduction of Se0to H2Se or through a direct reduction by CO2−.

Published
2023
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27. Solution-processible conjugated electrophosphorescent polymers

Author

Sandee, Albertus J., Williams, Charlotte K., Davies, John E., Kohler, Anna, Holmes, Andrew B., Evans, Nicholas R., Boothby, Clare E., and Friend, Richard H.

Subjects
Energy transfer -- Methods, Phosphorescence -- Analysis, Polymers -- Chemical properties, Chemistry
Abstract

The synthesis and photophysical study of a series of solution-processible phosphorescent iridium complexes are described. These covalently bound materials show improvements in efficiency over simple blends and will form the basis of future investigations into energy-transfer processes occurring in light-emitting diodes.

Published
2004

32. Synthesis of medium ring ethers. 5. The synthesis of (+)-laurencin

Author

Burton, Jonathan W., Clark, Stephen J., Derrer, Sam, Stork, Thomas C., Bendall, Justin G., and Holmes, Andrew B.

Subjects
Cyclic compounds -- Observations, Spectrum analysis -- Usage, X-ray crystallography -- Usage, Ring formation (Chemistry) -- Observations, Ethers -- Observations, Organic compounds -- Observations, Chemistry
Abstract

The key steps involved in the enantioselective synthesis of (+)-laurencin (1), achieved in 27 stages from (R)-malic acid (20), involved methylenation of lactone (49), intramolecular hydrosilation of enol ether (14) and a carbon homologation of diol (13). This gave a key ethyl substituted cyclic ether (59). 49 was obtained through Claisen ring expansion, alpha-hydroxylation and Yamaguchi lactonization. The synthesis of 1 was completed with an elaboration of the (E)-pentenynyl side chain and introduction of bromine.

Published
1997

35. Chemical tuning of the electronic properties of poly(p-phenylenevinylene)-based copolymers

Author

Burn, Paul L., Kraft, Arno, Baigent, Derek R., Bradley, Donal D.C., Brown, Adam R., Friend, Richard H., Gymer, Richard W., Holmes, Andrew B., and Jackson, Roger W.

Subjects
Polymers -- Research, Molecular electronics -- Observations, Chemistry
Abstract

Poly(p-phenylenevinylene) (PPV) based conjugated polymers have characteristic portions of high and low HOMO-LUMO gap energy which is chemically and electronically regulated using molecular engineering techniques. Two conjugated poly(arylenevinylene) related to PPV and MEH-PPV are used as light-emitting compounds in electroluminescent devices. Methoxy withdrawing groups in precursor polymers heated to a temperature of 220 degrees celsius effect the synthesis of these conjugated polymers. Partially conjugated polymers characterized by regions of high and low HOMO-LUMO gap energy is obtained during thermal treatment of precursor polymers. These partially conjugated polymers are 30 times more efficient than PPV in exhibiting electroluminescence.

Published
1993

41. Organic chemistry

Author

Holmes, Andrew B. and Stephenson, G. Richard

Subjects
Chemistry, Organic -- Research, Business, Chemicals, plastics and rubber industries
Published
1998

42. Organic chemistry

Author

Holmes, Andrew B. and Stephenson, G. Richard

Subjects
Chemistry, Organic -- Research, Business, Chemicals, plastics and rubber industries
Published
1996

44. A selection of recent topics from the chemical literature

Author

Stephenson, G. Richard, Holmes, Andrew B., and Burgess, Kevin R.

Subjects
Chemistry, Organic -- Bibliography, Chemistry, Inorganic -- Bibliography, Business, Chemicals, plastics and rubber industries
Published
1992

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