New Oxychalcogenides for Electronic, Magnetic and Optical Applications

固态化学对现代生活的许多领域产生了影响。例子不胜枚举：基本上，我们使用的所有汽油都是用固态多孔催化剂处理的;现代便携式设备中的燃料电池和可充电电池依赖于固态化学家生产的材料;金属合金和金属氧化物是所有电子产品的关键部件。今天使用的许多材料都是基于金属氧化物。在这些材料中，通常通过在结构中取代不同的金属离子来控制电子、光学和磁性。这会影响金属-氧反键带中的电子数，从而改变性质;化学成分中看似微小的变化可以显着改变材料的性质。在这项提案中，我们寻求资金，以调查化学的氧硫族化合物，同时含有O2-和S2-或Se 2-阴离子的阶段。我们认为这些材料令人兴奋的原因有几个。首先，它们是一个相对未被开发的家族，并且有很大的机会来制备具有受两种不同阴离子同时存在影响的性质的新材料。其次，在这种材料中的键合是显着不同的氧化物和较高程度的共价性导致在最高的能量占据的电子状态的金属和阴离子的组合特性。这提供了制备诸如p型透明导体的相的可能性，并生产具有潜在可开发的磁性的材料。第三，可以在材料中使用硫属化物层来稳定氧化物层，其结构布置在纯氧化物材料中不存在。在一个工作链中，我们的目标是开发与[Bi 2LnO 4][Cu 2Se 2]（Ln是3+镧系元素）相关的材料的化学。我们希望制备具有一系列潜在有趣特性的广泛的化学替代物和相关材料。第二条链靶向[Ln 2 O2 Q2][M2 O]（M是过渡金属）材料，其含有不寻常的[M2 O]原子层，其在结构上与许多重要材料中发现的层相关，但具有颠倒的M和O位置。我们希望探索可以制备的这种材料的范围，并研究它们的结构，磁性和电子特性。最后一项工作将利用我们对已知氧硫族化合物中发现的各种特征的了解来瞄准新的结构类型。总之，这个项目将使我们能够制备令人兴奋的新材料，并研究它们的结构，电子，光学和磁性。

Solid state chemistry has impact on many areas of modern life. Examples are numerous: essentially all the petrol we use has been processed using solid state porous catalysts; the fuel cells and rechargeable batteries in modern portable devices rely on materials produced by solid state chemists; metal alloys and metal oxides form key components of all electronic goods. Many of the materials in use today are based on metal oxides. In these materials electronic, optical and magnetic properties are usually controlled by substituting different metal ions in the structure. This influences the electron count in metal-oxygen antibonding bands which in turn changes properties; seemingly minor changes in chemical composition can dramatically change a material's properties. In this proposal we seek funding to investigate the chemistry of oxychalcogenides, phases which simultaneously contain O2- and S2- or Se2- anions. We believe that these materials are exciting for several reasons. Firstly, they are a relatively under-explored family and there are significant opportunities to prepare new materials with properties influenced by the simultaneous presence of two different anions. Secondly, the bonding in such materials is significantly different to that in oxides and the higher degree of covalency leads to a combination of metal and anion character in the highest energy occupied electronic states. This offers the possibility of preparing phases such as p-type transparent conductors and to produce materials with potentially exploitable magnetic properties. Thirdly, it's possible to use the chalcogenide layers in materials to stabilise oxide layers with structural arrangements that aren't found in pure oxide materials. The novel structures of such layers suggest novel electronic and magnetic properties may be discovered and exploited.In one work strand we aim to develop the chemistry of materials related to [Bi2LnO4][Cu2Se2] (Ln is a 3+ lanthanoid element). There are a wide range of chemical substitutions and related materials we hope to prepare with a range of potentially interesting properties. A second strand targets [Ln2O2Q2][M2O] (M is a transition metal) materials which contain an unusual [M2O] layer of atoms which is structurally related to layers found in many important materials but has M and O positions reversed. We wish to explore the range of such materials that can be prepared and investigate their structural, magnetic and electronic properties. A final strand of the work will use our knowledge of the kinds of features found in known oxychalcogenides to target new structure types.In summary, this project will allow us to prepare exciting new materials and investigate their structural, electronic, optical and magnetic properties.