The aim of the study is to analyze communication network configurations in volunteer online communities on the VKontakte social network and their relationship to forms of social capital and the prerequisites for organic solidarity. The analytical methodology is based on a comparison of the network configurations of volunteer online communities with forms of social capital and the preconditions for organic solidarity across five cities, accounting for differences in tie “depth” and small-world structure. The dataset covers the period from 2019 through August 2025. A network analysis of communicative activity (likes and comments) was conducted in regional online communities relevant to volunteering (Tyumen, Yekaterinburg, Perm, Ufa, Vologda). Structural characteristics of communicative-activity networks were computed; the distribution of activity among community members, the audience’s demographic profile, and the thematic differentiation of clusters were assessed. The methodological novelty lies in the interpretation of the relationship between clustering and modularity metrics, demonstrating the stability of thematically differentiated local communities. Interactions are dominated by “weak” ties (likes), whereas “strong” ties (comments) form dense local subnetworks. Territorial differences were identified in the salience of cluster structure and the concentration of activity. The networks display a pronounced core–periphery structure: a small group (2–5% of participants) generates a disproportionate share (30–50% or more) of all activity. This configuration reflects the specificity of online volunteer communities: a broad network with numerous nominal members and “weak” ties, within which a cohesive activist core sustains denser, trust-based ties. Practical recommendations are formulated to expand bonding and bridging social capital, and the small-world character of volunteer communities is demonstrated
Keywords
social networks, communication, solidarity, volunteering, network analysis, small world