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Over the past two decades, there has been an increased focus on designing STEM learning experiences for primary and second-level students. We posit that for teachers to design rich learning experiences for their students, they must first have the opportunity to develop their own STEM knowledge and competences, either during their pre-service teacher education or as part of their professional learning as in-service teachers. This systematic review of literature examines programmes which offer either pre-service or in-service teachers immersive learning experiences through placements in STEM roles in business or industry. A total of nine papers were identified in this review, featuring three unique programmes—one in the UK for pre-service teachers, and two in the USA involving in-service teachers. The findings indicate a variation in motivation and structures across the three programmes. The influence on teachers’ personal and professional development, and their intentions to change their classroom practices or behaviours to incorporate more ‘real-world’ contexts into their STEM learning activities, inspired by their experiences in industry, is discussed. This study presents recommendations for the design and implementation of immersive learning placements in industry to support STEM teacher professional learning, as well as suggestions for further studies to examine the influence on their classroom practice.

Schools are complex physical and social institutions within national education systems. They account for significant energy consumption and like other buildings can demonstrate inefficient patterns of energy use. Poor energy performance of educational facilities is an intricate issue driven by complex causality of interconnected and dynamic factors. Addressing this issue requires a systemic approach, which is heretofore lacking. The aim of this research is to present and describe a systemic framework to facilitate energy reduction in schools across different European contexts. This transdisciplinary approach to sustainable energy use has been piloted in 13 post-primary schools located in six countries in northwest Europe. The research implements a series of planned activities and interventions, which help to unveil a systemic approach to improving energy efficiency in schools. The findings demonstrate how this approach, together with its ensuing methodologies and strategies, can contribute to reducing carbon emissions and improve knowledge and awareness around sustainable energy.

This study reports on the implementation of a teacher professional learning programme designed to develop teachers’ competencies in designing rich tasks that support student learning across transitions in mathematics and physics. Primary and secondary teachers were supported to conduct their own Practitioner Inquiry (PI) and design and implement rich tasks in their classrooms. This study reflects on the experiences of four teachers of mathematics and physics who collaborated as part of a professional learning community over a nine-month period. The findings of this study were identified from analysing teachers’ reflections on their experiences of designing and implementing rich tasks in their classrooms and examining the impact of these tasks on their students’ learning through practitioner inquiry. Examples of rich tasks prepared by teachers will be discussed along with the challenges identified by teachers in carrying out practitioner inquiry and designing appropriate rich tasks.

This is the third volume in a series of handbooks published by the International Commission on Physics Education (ICPE) that aims to provide a structured, documented and critical review of extant Physics Education Research and serve as an important platform for discussion and debate on appropriate strategies and innovations in physics education. This volume is organized in six parts: Insights from Physics Education Research Contemporary Physics topics in the curriculum Students and teachers as learners in Physics Experimentation and Multimedia in Physics Education Designing and Evaluating classroom practices Learning in informal context and inclusion in Physics Education This handbook is of interest to physics teachers, teacher educators, education researchers, physicists, and policy makers interested in learning more about recent findings from physics education research and physics education practices., Published by the International Commission on Physics Education in cooperation with Euskal Herriko Unibertsitatea and Dublin City University.

Educational policies increasingly emphasise early childhood science engagement. As key influencers in children’s early learning, parents (n=85) attending a science workshop in three urban schools in Ireland were surveyed regarding their attitudes towards science. Seventy per cent of parents believed that science education should begin in the pre-school years, before the age of four. Despite high levels of education, at least half of the parents expressed some lack of confidence in talking about, and in doing science with, their young children. Parents who reported less confidence in doing science activities with their children also reported reduced frequency of activities for five out of the seven science learning opportunities listed. Mothers, compared to fathers, reported less confidence in doing science activities with their children. Findings indicate that parents’ confidence in science may impact early science experiences and highlight parents as a key support for increasing early science engagement.

The Inquiry-Based approach to Science Education (IBSE) is presented in scienti#c literature (Hake, 1998; Sharma et al., 2010) and in research projects reports (e.g. ESTABLISH, 2010; SAILS, 2014) as a credible solution to the reported lack of ef#cacy of more ‘traditional’ educative approaches, especially when focused on Research and Innovation (RRI) (Sutcliffe, 2006; IRRESISTIBLE, 2013; Ark of Inquiry, 2013). IBSE is an inductive approach to science teaching that considers direct experience at the center of learning. IBSE activities and strategies actively involve students in the identi#cation of relevant evidence, in critical and logical reasoning on the evidence collected and in re+ection on their interpretation. Students learn to conduct investigations, but are also led by the teachers to understand the typical processes scientists use to build knowledge. IBSE strategies are credited to improve student understanding in many conceptual #elds, due to their strongly contextualized nature, that focuses on the interdependence of situation and cognition, and on the ways they facilitate learning processes (Fazio, 2020) info:eu-repo/semantics/publishedVersion

It is widely acknowledged today that an Inquiry-Based approach to Research and Innovation processes can improve the interest of students in studying scientific topics. Such approaches can enable students to have the opportunity to interact with cutting edge topics, research results and work with researchers and other societal actors to better align research processes and their outcomes with the values, needs and expectations of today's society. However, there is still no clear consensus between researchers about the impact that inquiry-based approaches have on the student scientific knowledge and conceptual understanding at different ages and cultural levels. This paper discusses these aspects from a vertical and interdisciplinary curriculum perspective. Firstly, the impact of a series of inquiry-based learning activities on the acquisition of scientific knowledge and in the development of pupils' positive attitudes toward science in pupils aged 10–13 is discussed. Secondly, a discussion on important preconditions needed for an introduction of cutting-edge topics to the classroom, and the role of the inquiry that has to be offered to students to effectively construct knowledge is considered at the pre-university level. Following this, an approach adopted by three large scale European projects (ESTABLISH, SAILS and OSOS) that focus on enhancing science education curricula, pedagogy and assessment practices and supporting science educators in embedding Inquiry-Based Education or Responsible Research and Innovation principles in science education is presented. Finally, an innovative Doctoral Degree in Sustainability Science, which seeks transformative education that challenges the attitudes of both professors and students is presented and some of its most relevant aspects are discussed.

The Irish lower secondary science curriculum emphasises the development of scientific literacy through the use of inquiry teaching and learning approaches. The Science in Society Investigation assessment in this curriculum requires students to carry out inquiry into socioscientific issues (SSI). This research presents two case studies exploring how teachers used inquiry in the context of SSI for the development of students’ skills and knowledge. There were differences in the pedagogical approach adopted by the two teachers, including the level and type of inquiry and the SSI context chosen. In Clover Field School, the teacher facilitated open, experimental and discussion-based inquiry. The students developed skills of experimentation, with little focus on scientific knowledge in SSI contexts. In Daisy Park School, the teacher facilitated guided, research and discussion-based inquiry, placing a central focus on authentic SSI contexts. Students developed skills relating to research and critical evaluation of scientific evidence and scientific knowledge was demonstrated while considering societal implications. The two different pedagogical approaches led to the development of a range of skills and knowledge. Open and guided inquiry pedagogical approaches, experimental, discussion and research-based inquiry, were shown to complement each other in achieving the outcomes of the Irish lower secondary science curriculum.

This article reports on an investigation of a workshop approach to probe and deepen Irish preservice teachers’ (PSTs’) initial professional pedagogical vision of inquiry-based science education (IB...

IIn September 2020, Irish schools reopened following their emergency closure due to the COVID-19 crisis. Measures were put in place to minimise the risk of transmission of the virus within schools and communities. However, these measures were likely to impact on teachers’ capacity to facilitate learning in science, particularly the practical and investigative aspects of the Irish curriculum. This research explores the impact of the measures in place to limit virus transmission on teaching and learning in science, particularly on practical activities. The period of focus is the three months (September to November 2020) following the school closures. The research aims to highlight the implications of the COVID-19 crisis on science teaching and learning in Irish schools. The research will also provide recommendations to lessen the impact on primary and second-level science education to improve student learning and engagement in science.

Advances in science education research and development examining cognitive reasoning, epistemic practices, and formative and summative assessment tools and methods are fundamentally repositioning the conceptualization and design of curriculum, instruction, and assessment. However, with the rapid emergence of technologies and tools for supporting data analytics and data dashboards to inform and support classroom, school, and district level decision making, the accelerating pace of such changes is challenging teachers, school leaders, and education systems. New frameworks and methodologies while informing and guiding the study of educational systems (globally, nationally, regionally, and locally) are also challenging precepts and conceptions of recently rendered standards documents, curricular design models, and pedagogical practices. Yet another driver of change is the increasing orientations of schooling to address career and workforce initiatives. Recently released international policy documents are speculating on how models of education need to change in order to prepare students and citizens for life with uncertain global conditions and for workforce dynamics that are rapidly changing. A panel of international science education leaders were drawn together to examine and discuss recommendations from four 21st Century Education Policy reports. Two examining curriculum frameworks, one examining international assessments, and one examining instructional policies and teachers’ practices.

Over the last several years, active learning methods and strategies have received considerable attention from the educational community and are commonly presented in the related literature as a credible solution to the reported lack of efficacy of more “traditional” educative approaches. Research has shown that a possible factor is the strongly contextualized nature of active learning that focuses on the interdependence of situation and cognition. In this paper, we report the results of a Symposium with different contributions in the field of research on active learning. We start with a system analysis of the mental processes involved in learning physics which explains how active learning involves cognition followed by a response and feedback. Then, we describe a novel approach to active learning in which students participate in theatrical activities involving physics topics. Following this, we present experience of implementation of active engagement methods used in physics teacher preparation courses. Finally, a study is reported on an inquiry-based learning approach carried out in the context of socio-scientific issues with pre-service physics teachers.

This publication is the second report in a series of reports part of the Assessment of Transversal Skills in Science, Technology, Engineering and Mathematics (ATS STEM) project. The report is the result of an analysis of country responses to a survey launched in 2019, recording government responses to STEM policies and initiatives aimed at STEM education. The report is written within the framework of the ATS STEM project. The project is funded by Erasmus+ (Call reference: EACEA/28/2017 - European policy experimentations in the fields of Education and Training, and Youth led by high-level public authorities) and is an innovative policy experimentation project being conducted across 8 EU countries and involving a partner network of 12 educational institutions.

This research explored the impact of the COVID-19 crisis school closures on teaching and learning of science, with a focus on practical activities. In Ireland, practical activities and investigations are a curricular requirement. Findings from a survey carried out with primary and secondary teachers indicated the negative impact of the school closures on science learning and decreased facilitation of practical activities. Teachers reported a variety of barriers to student access and engagement, including lack of resources and technology in the home. This study highlights the risk that the COVID-19 school closures may increase pre-existing inequalities in science learning in Ireland.

This report (Report #5) was written as part of a research project titled, Assessment of Transversal Skills in STEM (ATS STEM). The project is funded by Erasmus+ (Call reference: EACEA/28/2017 - European policy experimentations in the fields of Education and Training, and Youth led by high-level public authorities). Thedevelopment of the ideas, concepts and understandings presented in this final report isvisually synthesised in Towards the ATS STEM Conceptual Framework. Towards the ATS STEM Conceptual Framework aims to inform the classroom practices of integrated STEM education topics and their assessment. Educators can benefit from such a conceptual framework encapsulating the key ideas from the literature and that helps to inform their understanding and subsequent classroom practice.

The numbers of students studying physics at upper second level and the low numbers of teachers qualified to teach physics at second level are a matter of concern for the future of STEM education in Ireland and internationally. This study describes a national collaboration focussed on addressing teacher’s approaches to the teaching and learning of physics at lower second level, raising awareness of physics/STEM careers and examining teachers’ and students’ academic resilience and unconscious biases. The findings report on the design and implementation of a physics teacher professional development programme with all lower secondary science teachers from seven Irish second-level schools.

Data on gender and physics in Ireland at school, third level (which includes institutes of technology and universities), and in research are presented.

Recent research has focused increasingly on student-led inquiry into socio-scientific issues (SSI) as a way of developing the skills and knowledge of science in secondary school students. However, there are barriers for teachers implementing this type of inquiry such as lack of pedagogical skills. This study explores the experiences of pre-service teachers (PSTs) as they engage in student-led, research-based inquiry in the context of SSI relating to the societal implications of a technological application of science. It is proposed that through engagement in this type of inquiry as learners that the PSTs will develop the skills and knowledge of science and overcome some barriers to implementing inquiry in their own teaching practice. 43 PSTs completed an open-ended questionnaire relating to their experience and their answers were subject to thematic analysis. Findings indicate that the PST experience focused on development of research and presentation of evidence. When demonstrating their knowledge, the PSTs did so within the context of the SSI. Implications for the implementation of inquiry in the context of SSI in secondary schools and for initial teacher education are discussed.

Over the past half-century free secondary level education has been introduced in the Irish education system and as a result a steady increase in the number of students completing a third level education has been observed. In tandem with this widening participation in second level education, curricula have been adapted to accommodate the varying needs and abilities of students while at the same time, addressing the changing role of science education in the national economy. Between 1966 and 2016, three different physics syllabi have been implemented at the upper secondary level in Irish schools. The focus of this study was to examine what were the cognitive demand of the Leaving Certificate Physics examination questions from 1966-2016. Bloom’s Taxonomy of Educational Objectives was used as a classification tool of the level of cognitive demand in the analysis of the examination question parts, as it has been used by the Irish Department of Education in the preparing the examination questions. A sample of nine Leaving Certificate Physics examination papers were selected as representative samples of the three syllabi spanning the fifty years. Despite clear changes in the three physics syllabi over the fifty year period with changes in examination question style, there was not a notable change in cognitive domains of examinations papers. All question parts were classified according to four levels of cognitive demand with the cognitive domain ‘remember’ coded most frequently (ranging from 73% in 1967 to 46% in the 2008 examination). Notably, none of the nine examination papers examined in this study contained questions (or question-parts) which coded for the cognitive domains of ‘evaluate’ or ‘create’.

An interdisciplinary science course has been implemented at a university with the intention of providing students the opportunity to develop a range of key skills in relation to: real-world connections of science, problem-solving, information and communications technology use and team while linking subject knowledge in each of the science disciplines. One of the problems used in this interdisciplinary course has been selected to evaluate if it affords students the opportunity to explicitly display problem-solving processes. While the benefits of implementing problem-based learning have been well reported, far less research has been devoted to methods of assessing student problem-solving solutions. A problem-solving theoretical framework was used as a tool to assess student written solutions to indicate if problem-solving processes were present. In two academic years, student problem-solving processes were satisfactory for exploring and understanding, representing and formulating, and planning and ...

This chapter discusses the outcomes of a pan-European collaboration to support teachers in adopting inquiry based science education (IBSE) and in assessing their student’s inquiry skills and competences in classroom practice. The project, Strategies for Assessment of Inquiry Learning in Science (SAILS), involved a team of science teacher educators and second level science teachers from across twelve European countries—Belgium, Denmark, Germany, Greece, Hungary, Ireland, Poland, Portugal, Slovakia, Sweden, Turkey, United Kingdom. Through sustained collaboration between science teachers and educators and across borders, both classrooms and countries, a variety of teaching and assessment strategies that facilitate inquiry learning in the classroom have been highlighted.

We report on semi-quantitative research into students' difficulties with integration in an intermediate-level electromagnetism course with cohorts of about 50 students. We have found that before they enter the course, students view integration primarily as a process of evaluation, even though viewing integration as a summation process would be more fruitful. We confirm and quantify earlier results that recognizing dependency on a variable is a strong cue that prompts students to integrate and that various technical difficulties with integration prevent almost all students from getting a completely correct answer to a typical electromagnetism problem involving integration. We describe a teaching sequence that we have found useful in helping students address the difficulties we identified.

There are specific mathematical tools involved in building an accurate model of introductory electric field theory. Algebra operations, vectors, field lines, proportional reasoning and the inverse square law are all integral parts of gaining a complete understanding of an electric field. In this paper we present a small body of research, taken from a case study with a group of 14 upper second level students, in which they developed their understanding of the inverse square law, using a pre-test-tutorial-post-test tutorial lesson model. Students struggle to understand the inverse square law unless they are repeatedly exposed to it. Using the context of intensity, our students develop their understanding of the inverse square law using a variety of representational forms, such as diagrammatic, tabular / graphical and calculations using formulae. Using our pre-test and post-test results, our students showed gains in their reasoning used to explain the variation of intensity when an object is moved various distances from a source, which we attribute to their reasoning developed in the tutorial lessons. Additionally, students completed quantitative problems involving the inverse square law in the context of Newton’s gravitational law. Six weeks after the completion of the inverse square tutorial, our students completed a tutorial lesson, in which they applied their understanding of the inverse square law to Coulomb’s law and the electric field. Our results show that our students could apply the inverse square law to these contexts when guided, but some difficulties still remained, such as proportional reduction / increase based on variation of the distance, and transfer between representations, such as algebraic to graphical.

Low Energy Electron Diffraction (LEED) and Density Functional Theory (DFT) have been used to analyse the structure of Cu{100}-p(2 × 6)-2mg-Sn at room temperature. In this work we found that the favoured geometry for this 0.33 ML Cu{100}-Sn phase is a combination of an overlayer structure and a surface alloy; two Sn atoms are alloyed in to the first copper layer and the other two Sn atoms adsorb at off symmetry hollow sites. In order to relieve the stress in the alloyed layer, the alloyed Sn atoms are buckled 0.59/0.45 ± 0.2 A (DFT/LEED) above the centre of mass of the first layer copper atoms.

The ESTABLISH FP7-funded project is involved with development and implementation of professional development workshops to support teachers in adopting more inquiry based approaches in their teaching. Identifying teacher views, goals, practices and the challenges they face in implementing inquiry activities, can inform teacher educators of the needs of their participating teachers. This can also inform them to provide the appropriate support in order to help teachers overcome obstacles and develop their own practice in inquiry. This paper outlines the initial results from a profiling instrument used to examine teachers’ beliefs about IBSE, attitudes to teaching science and teaching by inquiry and some ideas about their current practices. The data presented in this paper outlines the profile of the teachers when they came to the first of the ESTABLISH teacher workshops in a number of European countries. This paper outlines a summary of the development of the evaluation tool, how the evaluation data was collected and analysed and highlights the key findings. FP7SiS project (ESTABLISH) CSA-SA Project No 244749

Physics is contributing strongly to the national Irish economy, with 4.5% of the Irish workforce employed in physics-based or other science, technology, engineering, and math (STEM) sectors. However, a recent national report reveals that the proportion of women working in jobs that utilize STEM skills is less than 25% of the workforce. We present data collected from the views of 1,000 female secondary school students, young women (age 18–23), secondary-school teachers and parents on what influences secondary school students’ choices of subjects and in particular STEM-related subjects. In addition, benchmarking data on female student and staff ratios for the past five years is presented from all seven Irish university physics departments.

During the period 2008–2014, the European Commission funded several large-scale projects in science education that promoted the use of inquiry-based learning for engaging young people in science. All these projects were aimed at the introduction and broader use of inquiry-based science education (IBSE) through enriching the skills of teachers by delivering appropriate teacher education programs at both pre-service and in-service levels. This paper will present on the approach adopted by the SAILS project to support science teachers in the use and dissemination of Inquiry based approaches in their own classrooms with students aged 12–18 years.

The geometrical structure of 0.50 ML Sn adsorbed on Cu{1 0 0} surface has been studied using Symmetrized Automated Tensor LEED. At this coverage, a p( 3 2 × 2 )R45° ordered surface structure is formed. The favoured structure is a substitutional surface alloy, that includes a missing row reconstruction. This structure might have originated a from c(2 × 2) superstructure. The p( 3 2 × 2 )R45° phase is formed by bringing pairs of Sn atoms together in the Cu{1 0 0}-c(2 × 2)–Sn alloyed top layer and removing every third row of copper in the top layer. The two in-equivalent tin atoms in the first layer are buckled towards the solid-vacuum interface by 0.39/0.27 ± 0.07 A with respect to the first layer copper atoms. The buckling between the Sn atoms is 0.12 ± 0.08 A. The lateral displacement of Sn atoms is of magnitude 0.26 ± 0.10 A. The first interlayer spacing is expanded by 4% with respect to the bulk value. Pendry reliability factor has been used to measure the level of agreement between theory and experiment giving a moderate value of 0.26 for the favoured structure.

Low energy electron diffraction (LEED), scanning tunneling microscopy (STM) and the normal incidence X-ray standing wave (NIXSW) technique have been used to determine the structure of the first surface phase formed on Cu{1 0 0} upon deposition of 0.21 monolayers (ML) of tin. At this coverage the LEED images exhibits a modified p(2 × 2) structure with split fractional order diffraction spots. A double scattering LEED pattern simulation consistent with both the Sn surface coverage and the complex split beam LEED pattern suggests an ordered phase based on a p(2 × 2) structure with light anti-phase domain walls. Possible adsorption sites are identified from NIXSW data by triangulation of the distances between the Sn atoms and the (2 0 0) and (1 1 1) planes. The results indicate that Sn atoms adsorb in a fourfold site but does not distinguish between overlayer and substitutional sites. The STM data reveal small domains of p(2 × 2) structure formed by the Sn atoms being adsorbed in substitutional sites. These domains typically contain 16 Sn atoms arranged in a square 4 × 4 array, however larger and smaller rectangular domains are also observed with sides containing three, five and six Sn atoms. The width of the domain wall is found to vary with rows of one, three or five copper atoms separating the domains in both the [0 1 1] and [ 0 1 1 ] directions. The STM images indicate that the Cu atoms in the domain walls are vertically displaced from their expected positions. This is attributed to elastic strain due to the large metallic diameter of Sn (0.162 nm) relative to Cu (0.127 nm).

The coverage dependent structural phase transitions of Sn on Cu {1 0 0} have been re-examined by low energy electron diffraction (LEED). Double scattering LEED pattern simulations have been applied both to a range of possible new models and to previously suggested structures with the aim of identifying the most likely surface geometries throughout the sub-monolayer coverage regime. A model consistent with both the Sn surface coverage and the complex split beam LEED pattern observed has been suggested for the low coverage (θSn=0.21 ML) ordered phase based on a p(2×2) structure with “light” antiphase domain walls. We also demonstrate that higher coverage p(2×6) (θSn=0.37 ML) and p(3√2×√2)R45° (θSn=0.50 ML) structures based on c(2×2) local periodicity yield a consistent explanation of the LEED data. While the simulations identify likely structures, the limitations of this approach mitigate against definitive structural assignments. However simulations for models based on c(2×2) structures incorporating defects in the form of periodic density modulations combined with substrate reconstruction lead to an enhanced agreement with observed LEED data compared to overlayer models previously suggested.

Organisational semiotics provides methods for understanding complex problems. This paper proposes the use of the organisational semiotic onion to understand and address the complex information management requirements of upstream oil and gas capital projects. Some of the project information management challenges experienced by one company are presented using the organisational semiotic onion. This approach shows the benefits of using the onion as an analytical method for analysing information management requirements as requirements can be holistically analysed and addressed at informal, formal and technical layers.

Core-level photoemission spectra of the As 3d, Ga 3d and Bi 5d core levels were recorded for the BiGaAs (111)A-(2×2) surface. From the early stages of Bi growth, there are two distinct chemical environments for Bi. Surface Bi is bonded to both As and Ga atoms. The deposition of approximately 1 ML of Bi removes the dangling bonds from the surface As and Ga atoms, which are associated with the (2×2) vacancy-buckling structure. Annealing to 350°C reverses this process and surface dangling bonds for Ga reappear. When the Bi had fully desorbed at 425°C, photoemission and LEED results showed that the surface recovers the (2×2) vacancy structure but with a larger degree of surface disorder than that found before the deposition of Bi.

We present statistics on the current representation of female physics students, teachers, and researchers at secondand third-level education in the Republic of Ireland. Our findings show that girls who take physics in secondary (high) school represent less than 4% of all students who complete their secondary school studies. At third-level the situation is also grim, with some institutes reporting less than 7% female participation in physicsbased courses. We also present Institute of Physics findings on the female percentages at the different academic career levels for some of the major third-level institutes in Ireland. These show that women are underrepresented at all levels. We report on initiatives that have been launched by Science Foundation Ireland under its Women in Science and Engineering Programme. These aim to address the lack of women in the science and engineering sectors and encourage qualified women back into the academic arena.

The coverage‐dependent structural phase transitions of Sn on Cu100 have been by low‐energy electron diffraction (LEED), scanning tunneling microscopy (STM), and x‐ray standing wave spectroscopy (XSW). Dynamical LEED calculations have been applied both to a range of possible models and to previously suggested structures with the aim of identifying the most likely surface geometries throughout the sub‐monolayer coverage regime. A model consistent with both the Sn surface coverage and the complex split‐beam LEED pattern observed has been suggested for the low coverage (qSn = 0.21ML) ordered phase based on a p(2′2) structure with “light” antiphase domain walls. We also demonstrate that higher coverage p(2×6) (qSn = 0.37ML) and p(3O2′O2)R450 (qSn = 0.50ML) structures based on c(2′2) local periodicity yield a consistent explanation of the higher‐coverage LEED data. The 0.5‐ML coverage has been studied using symmetrized automated tensor LEED, which shows that this phase is formed by bringing pairs of Sn atoms to...

We have investigated the decapped GaAs(311)A surface using both scanning tunneling microscopy and synchrotron-radiation photoemission. While our data are in broad agreement with the structural model of GaAs(311)A proposed in a recent study [Wassermeier et al., Phys. Rev. B 51, 14 721 (1995)], we find considerable differences in the surface order. In particular, the As dimer rows are unbroken over much shorter length scales and are highly kinked. We observe a correspondingly lower degree of anisotropy in the surface roughness than that previously reported. An (8\ifmmode\times\else\texttimes\fi{}1) reconstruction was not observed. An analysis of As 3d and Ga 3d core-level photoemission spectra suggests that surface As atoms are in only one bonding configuration while surface Ga adopts two different bonding states. We discuss possible origins for the core-level spectra surface components.

The surface structures resulting from the deposition of Sb on the GaAs(111)B-(2 × 2) surface at room temperature followed by annealing, have been studied by high-resolution soft X-ray photoemission (SXPS) and low energy electron diffraction (LEED). For depositions at room temperature with no subsequent anneal and for annealing temperatures up to 300°C, Sb islands are formed between which the As trimer-based (2 × 2) substrate reconstruction of the clean GaAs surface is observed. Annealing to temperatures between 350 and 475°C leads to the creation of Sb chain pairs coexisting with regions of Sb trimers. At 500°C an ordered surface is produced, associated with Sb trimers and an As vacancy.

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