Understanding how people coordinate social interactions in public spaces is central to environmental psychology's study of human-environment relations, but research findings remain fragmented across disciplinary traditions with different epistemologies and vocabularies. This meta-narrative review synthesizes scholarship from ecological and environmental psychology, micro-interactional studies of public life, environment-behavior studies, and spatial justice and political recognition. We conducted iterative searches across Web of Science and Scopus (1908-2025), supplemented by forward-backward citation tracking; searching continued until new iterations introduced no new explanatory framework, citation lineage, or mode-relevant distinction. The final corpus comprises 119 key publications from 100 scholars that explicitly explore social interaction modes, types, or thresholds. Analysis reveals convergence on six recurring modes of public interaction: withdrawal, co-presence, co-attention, co-exchange, co-action, and assembly. The review compares how each tradition defines these modes and marks boundaries and shifts between them, preserving differences in explanatory approach. The framework provides a comparative vocabulary linking core concepts such as affordances, privacy regulation, joint attention, and attentional restoration to sociological, urban, and political accounts of public interaction. Analyzing spatial, normative, perceptual, and political conditions, the framework clarifies why similar spatial provisions can produce different interactional possibilities. ... Read more

Children’s playgrounds are everyday environments in which social interaction unfolds without fixed roles, predefined shared goals, or institutionalized coordination. While ecological psychology has developed rigorous accounts of social affordances in structured, multi-agent contexts such as sport, less is known about how social affordances are realized in open-ended peer interaction. This study examines how opportunities for social engagement emerge, stabilize, and dissolve through children’s spatial-interactional practices during recess in a Dutch primary school playground. Using micro-observational video analysis of 72 children (ages 5–12), we first assess the applicability of sport-derived social affordance categories to unstructured playground interaction. We then analyze episodes that resist categorical description to identify process dimensions through which social affordances are realized over time. The analysis yields four interrelated dimensions—initiation mechanisms, spatial-social coupling, participation diversity, and temporal dynamics—that specify how children negotiate access to interaction through movement, positioning, and responsiveness to peers and material features. These findings reconceptualize playground social affordances as spatially and temporally unfolding interactional achievements and suggest a shift in research focus toward examining how children negotiate access to social engagement. ... Read more

Cationic silver hydride clusters (Ag_nH⁺) can be formed by a number of physical and chemical processes, holding great promise for a range of applications including photonics, catalysis, sensing, and biomedicine, among others. Here, we present a comprehensive theoretical investigation of Ag_nH⁺ clusters (n = 1–7) using highly accurate coupled-cluster (CC) theory. Multiple low-lying isomers are identified using CC theory with single and double excitations (CCSD), whereas their relative stabilities are determined with the more accurate CCSD(T) method. The CCSD(T) results predict a pronounced odd–even alternation in relative stabilities, with Ag₂H⁺ being the most stable species, which is consistent with experimental mass spectrometry measurements. Ab initio molecular dynamics simulations show that all low-energy isomers remain structurally rigid at room temperature, whereas bonding analyses (frontier molecular orbitals, natural bond orbital, molecular electrostatic potential, quantum theory of atoms in molecules, non-covalent interaction) indicate strong ionic Ag–H interactions, weak non-covalent Ag–Ag interactions, and significant donor–acceptor stabilization in larger clusters. Electrical mobilities of these clusters, computed by the trajectory method, were labelled on experimental spectra, in order to contribute towards their interpretation. Overall, our results resolve inconsistencies from prior theoretical predictions, provide a rigorous description of cationic silver hydride clusters, and are used to improve the interpretation of earlier observations. ... Read more

Affordances—the action possibilities provided by the environment—are a central notion in ecological psychology, offering valuable insights into dynamic user-environment interactions. In recent years, affordance theory has gained traction in architecture and design for its potential to illuminate how users perceive and engage with built environments, informing both design thinking and performance evaluation. Despite this growing interest, its application within architectural design research remains limited. This article introduces an affordance-based evaluation framework developed to analyze how built environments enable or constrain adaptive user behaviors. Grounded in ecological psychology and architectural theory, the framework provides a structured approach for assessing usability, anticipating behavioral variability, and aligning design outcomes with diverse user needs. By explicitly linking architectural intention with situated user-environment interaction, the framework contributes a design-oriented methodology for improving responsiveness, inclusivity, and the adaptive capacity of the built environment throughout its lifecycle. ... Read more