What are Microstructures?
Microstructures are the way you organize all your routine interactions. They guide and control how groups work together. They shape your conversations and meetings. The five most commonly used microstructures are presentations, open discussions, managed discussions, status reports, and brainstorming sessions.
What elements define design of Microstructures and how Liberating Structures?
A structuring invitation (listen to me);
How the space is arranged and what materials are needed (rows or U facing presenter, screen, projector and PPT slides);
How participation is distributed (nearly 100% of total time for presenter);
How groups are configured (one group, one presenter); and,
A sequence of steps and time allocation (presentation for most of time; possibly Q&A for balance of time).
Liberating Structures are designed with variations on these five structural elements. There are total 33.

What are Liberating Structures?
Liberating Structures are easy-to-learn microstructures that enhance relational coordination and trust. They quickly foster lively participation in groups of any size, making it possible to truly include and unleash everyone. Liberating Structures are a disruptive innovation that can replace more controlling or constraining approaches.
Excerpts from:
https://www.liberatingstructures.com