Castep: Advanced spectroscopies using high-performance computing

随着理论和计算的最新进展，我们已经能够从第一原理计算凝聚态系统的性质。人们甚至可以希望做到这一点，这要归功于量子力学描述化学键的准确性。狄拉克的一句杜撰的俏皮话说，在发现量子力学之后，剩下的就是化学：如果一个人能解出某个东西的薛定谔方程--一个原子、一个分子、原子在固体或液体中的集合--一个人就能预测出每一种物理性质。狄拉克的陈述并没有显示出做剩下的事情有多么困难，而且它花费了巨大的努力和巧妙地将我们带到了以合理的精度计算材料的一些性质的点上。模拟对我们思考凝聚态问题的影响是巨大的。然而，CASTEP程序试图只使用量子力学(特别是密度泛函理论)来计算材料的许多性质。CASTEP是一个功能丰富的第一原理电子结构程序，因此它的功能非常多。为了从第一原理计算系统的任何物理性质，基本量是从其推导出许多其他量的总能量。在这里，我们希望进一步开发CASTEP的应用程序范围，Making对于更广泛的科学家来说是有价值的，这将使他们能够以快速、可靠和准确的方式进行研究。它是专门为在高性能计算机上使用而设计的，从头开始编写时考虑到了多核体系结构。CASTEP是英国超级计算设施Hector上使用最多的代码之一。我们的目标是开发一系列令人兴奋的新光谱工具，这些工具将在理论/计算凝聚态物质和实验技术之间形成紧密的联系。对实验光谱数据的解释并不简单，但如果建立在坚实、准确的理论基础上的软件可以用来生成这样的数据，那么就可以直接与实验进行比较，并允许对结果进行详细的解释。这就是当前提案的目的。在整个过程中，我们将保持最高质量的代码设计/实现和测试技术，就像我们过去一贯做的那样。在这项工作结束时，我们将在CASTEP中拥有新的功能，这将产生新的科学。另一项建议(本次召回的第二阶段)将用于制定质量代码，使其能够广泛使用。

With recent theoretical and computational advances we have been able to calculate the properties of condensed matter systems from first principles. That one can even hope to do this is down to the accuracy of quantum mechanics in describing the chemical bond. Dirac's apocryphal quip that after the discovery of quantum mechanics the rest is chemistry sums it up: if one can solve the Schrodinger equation for something - an atom, a molecule, assemblies of atoms in solids or liquids - one can predict every physical property. Dirac's statement doesn't quite show how difficult doing the rest is, and it has taken great effort and ingenuity to take us to the point of calculating some of the properties of materials with reasonable accuracy. The impact of simulations on our thinking about condensed matter problems is immense. However, the CASTEP code attempt to calculate many properties of materials using only quantum mechanics (in particular, density functional theory).CASTEP is a richly featured first principles electronic structure code and as such its capabilities are numerous. Aiming to calculate any physical property of the system from first principles, the basic quantity is the total energy from which many other quantities are derived. Here we wish to develop CASTEP's range of applications further, making is valuable to a much wider range of scientists which will enable them to perform their research in a fast, reliable and accurate manner.It has been designed specifically for use on high-performance computers, being written from the ground up with a many-core architecture in mind. Castep is one of the most used codes on the UK supercomputing facility, HECToR. We aim to develop an exciting range of new spectroscopic tools that will form a close link between theoretical/computational condensed matter and experimental techniques. Interpretation of experimental spectroscopic data is not straightforward, but if software that is build on a firm, accurate theoretical foundation can be used to generate such data, then direct comparison to experiment can be performed and allow detailed interpretation of the results to be done. This is the aim of the current proposal. Throughout we will maintain the highest quality code design/implementation and testing techniques, as we have consistently done in the past. At the end of this work we will have new functionality in CASTEP that will produce new science. A further proposal (stage 2 of this call) will be used to make the code of a quality such that it can be widely used.