How did Leibniz’s monads differ from material atoms?

In Gottfried Wilhelm Leibniz’s monadology, monads differ fundamentally from material atoms in their nature, composition, and properties:

• Immateriality vs. Materiality: Unlike material atoms, which are physical particles possessing size and shape, monads are immaterial substances that lack spatial extension.12
• Unity and Divisibility: Leibniz argued that material atoms are not true unities because they remain divisible in principle. In contrast, monads are the ultimate, indivisible constituents of reality—metaphysical points of existence.3
• Nature: While material atoms are physical, monads are conceived as dynamic, soul-like entities. Each monad is a center of action gifted with perception, mirroring the universe from its own unique perspective.231
• Relationship: Material objects are not composed of physical parts in the traditional sense; rather, they are appearances derived from collections of these immaterial monads. While material atoms interact through physical contact, monads have no true causal relations with one another, existing instead in a state of preestablished harmony orchestrated by God.2