Why technetium and manganese have low melting and boiling point?

Answer 1

Because of stable electronic configuration of Mn electrons are less delocalized and hence they cannot move in electron sea freely to contribute to strong metallic bond. Hence they have low melting points.

Answer 2

Technetium and manganese have low melting and boiling points because of their relatively weak metallic bonding. The interatomic forces in these elements are not as strong as in other metals, leading to lower melting and boiling temperatures. Additionally, their atomic structures and electronic configurations contribute to their lower melting and boiling points compared to other metals.