The idiomatic expression "kind of chemistry" is used to describe a certain type or quality of interaction between two people, often indicating that there is an unspoken connection or attraction between them. Full definition
There isn't a set pattern for a successful first date conversation; it all depends on who you're with and what kind of chemistry there is between you. (eharmony.co.uk)
Our goal is a different kind of chemistry altogether. (elitesingles.com)
Luckily two leads have some odd kind of chemistry. (flicks.co.nz)