Basic and applied research in materials science plays a significant role worldwide and it is therefore no wonder that the materials research scene in Israel is thriving. In fact, Israeli researchers in materials science have been recognized by many national and international awards, which are far too numerous to be discussed here. It suffices to mention the Nobel Prize awarded to Prof. Dan Shechtman for his discovery of quasicrystals. While many aspects of materials science are practical in nature, understanding and designing materials properties rely heavily on fundamental scientific research, leading to an increasing involvement of computational and theoretical chemistry and physics. Indeed, an independent area – computational materials science – has arisen and has become commonplace in materials research. This special issue highlights computational materials science work done in Israel.

Theory and computation in science in Israel have a long tradition, making first strides into biology over 50 years ago. Notably, a major step in enabling the leap from basic theoretical chemistry and physics to computational research came in the late 1960s, when Lifson and Warshel of the Weizmann Institute of Science developed the first molecular force field that was applicable to organic molecules. This work was also enabled by the acquisition of a powerful computer for that time, named the Golem (after the automaton from Jewish folklore). Initially, these calculations targeted small organic molecules, but in 1969 Levitt and Lifson used force fields to perform the first energy minimization of simple protein structures. At the time, Karplus, who was an established theoretical chemist and physicist at Harvard University, joined the Lifson group at the Weizmann Institute for a six‐month Sabbatical. Hence, the first contact between the Nobel Prize trio of 2013 – Karplus, Levitt, and Warshel – was made in Israel.

Around the turn of the 21^st century, an increasing number of new research groups in Israel have focused their attention on understanding materials, using a wide variety of first principles, empirical, and model calculations. The important role played by theory and computations in materials science in Israel is now well reflected by the their presence at a variety of academic institutions, including (in alphabetical order) Ariel University, Bar‐Ilan University, Ben‐Gurion University, the Hebrew University in Jerusalem, the Technion – Institute of Technology, Tel‐Aviv University, and the Weizmann Institute of Science. In most cases, pertinent groups are not only an integral part of materials science departments, but are also well represented in chemistry, physics, and relevant engineering disciplines. Many of the above academic institutions are continuing to hire talented faculty members that specialize in theory and computation of materials, assuring a bright future for the field in Israel.

Glancing at the breadth of topics covered in this issue provides a glimpse at the multifaceted research taking place in the field of theoretical and computational materials science in Israel. Necessarily, the collection of articles presents but a partial view of the work carried out, as some groups could not contribute an article to this collection and others are engaged in more than one research theme. Even so, it is clear that on the one hand the research involves development of fundamental theory and computational methods and on the other hand it entails application of the theory and methods to a wide range of problems at the forefront in materials science.

This Special Issue includes twelve contributions: seven review articles and five original research articles. Among the Review articles, Amouyal and co‐workers present a review of first‐principles studies of polaron transport in solids; Martin and Santra contribute a comprehensive review of empirical double‐hybrid density functional theory (DFT) methods, comparing their performance with wave function theory and standard lower‐rung DFT methods; Kraisler reviews the asymptotic behavior of exchange‐correlation energy density and potential in DFT, presenting exact results as well as approximation strategies; Grinberg presents a review of first‐principles studies of band engineering in ferroelectric oxides; Cohen and Diéguez present electronic structure calculations of supertetragonal phases of perovskite oxides; Stein and Jose contribute a computational study relevant to astrochemistry, focusing on molecular formation upon ionization of van der Waals clusters; and Major and co‐workers present a review of computational studies of layered cathode materials in Li‐ion batteries.

Among the Research Articles, Natan and co‐workers present a DFT study of the electronic and magnetic properties of Cu₂MgO₃; Kronik and co‐workers provide a comparative study of dispersion‐augmented DFT calculations of Fe‐porphyrin on Co(001) and Cu(001); Makov and co‐workers present materials modeling of π‐phase monochalcogenides; Caspary Toroker and co‐workers report a comparative study of charge transport along two‐dimensional metal/semiconductor/metal systems; and Eidelstein et al. present a first principles investigation of cold curves of metals using different approximations of DFT, compared with experimental data.

We hope that the articles within this Special Issue will prove to be useful and will spur further exciting research in Israel and worldwide.

材料科学的基础研究和应用研究在世界范围内发挥着重要作用，因此，以色列的材料研究领域正在蓬勃发展也就不足为奇了。实际上，以色列的材料科学研究人员已获得许多国家和国际奖项的认可，这些奖项太多了，在这里不予讨论。只需提及因发现准晶体而授予丹·谢赫特曼教授的诺贝尔奖就足够了。尽管材料科学的许多方面本质上都是实用的，但了解和设计材料属性在很大程度上依赖于基础科学研究，从而导致计算和理论化学与物理学的介入日益增加。实际上，已经出现了一个独立的领域-计算材料科学-并在材料研究中变得司空见惯。

以色列的科学理论和计算历史悠久，距今已有50多年的历史。值得注意的是，在实现从基础理论化学和物理学到计算研究的飞跃方面迈出的重要一步是在1960年代后期，当时魏茨曼科学研究所的Lifson和Warshel开发了第一个适用于有机分子的分子力场。当时还购置了一台功能强大的计算机Golem（以犹太民俗学的自动机命名），从而使这项工作成为可能。最初，这些计算针对的是有机小分子，但在1969年，Levitt和Lifson使用力场对简单的蛋白质结构进行了首次能量最小化。当时，卡尔普斯（Karplus）是哈佛大学的一位公认的理论化学家和物理学家，加入了魏兹曼学院的利夫森小组，为期六个月的放假。因此，2013年诺贝尔奖三人组（Karplus，Levitt和Warshel）首次在以色列接触。

在21^世纪之交世纪，以色列越来越多的新研究小组将注意力集中在使用各种第一性原理，经验和模型计算的理解材料上。以色列材料科学中的理论和计算所发挥的重要作用，现在已经很好地体现在它们在各种学术机构中的存在，包括（按字母顺序）阿里尔大学，巴伊兰大学，本古里安大学，希伯来大学在耶路撒冷，特拉维夫大学理工学院-技术学院和魏兹曼科学研究所。在大多数情况下，相关的小组不仅是材料科学系的组成部分，而且在化学，物理和相关工程学科中也有很好的代表。

浏览本期涵盖的主题范围，可以一窥以色列在理论和计算材料科学领域中进行的多方面研究。必要的是，文章集仅呈现了所进行的工作的部分视图，因为某些小组无法为该集锦贡献文章，而另一些小组则从事多个研究主题。即使如此，很明显，一方面，该研究涉及基础理论和计算方法的发展，另一方面，它涉及将理论和方法应用于材料科学中最广泛的问题。

本期特刊包括十二篇文章：七篇评论文章和五篇原创研究文章。在评论文章中，Amouyal及其同事对固体中极化子迁移的第一性原理研究进行了综述。Martin和Santra对经验双混合密度泛函理论（DFT）方法进行了全面综述，将它们的性能与波动函数理论和标准的低阶DFT方法进行了比较；Kraisler回顾了DFT中交换相关能量密度和势的渐近行为，给出了精确的结果以及近似策略；格林伯格介绍了铁电氧化物中能带工程的第一原理研究。科恩和迪格斯介绍了钙钛矿氧化物超四方相的电子结构计算。斯坦（Stein）和何塞（Jose）进行了与天体化学有关的计算研究，重点研究了范德华簇团电离后的分子形成；Major和他的同事对锂离子电池中分层阴极材料的计算研究进行了综述。

在研究文章中，Natan和他的同事介绍了对Cu ₂ MgO ₃的电子和磁性的DFT研究。Kronik及其同事对铁卟啉对Co（001）和Cu（001）的弥散增强DFT计算进行了比较研究。Makov及其同事介绍了π相单硫属元素化物的材料模型。Caspary Toroker及其同事报告了沿二维金属/半导体/金属系统的电荷传输的比较研究。和Eidelstein等。与实验数据相比，本文介绍了使用不同DFT近似值的金属冷曲线的第一个原理研究。

我们希望本期特刊中的文章能被证明是有用的，并能刺激以色列乃至全世界的激动人心的研究。