# Dopants at adjacent sites. Probability. Solid State Physics.

1. ### theleftside

2
Hi,

Could someone explain how to calculate the probability that two substitutional dopants will reside in adjacent lattice sites.

For example, given a dopant concentration of 5% and a crystal structure in which each lattice site/atom is coordinated to 8 others what is the probability of finding two dopant atoms residing in adjacent lattice sites?

Thanks for any insight!

2. ### Claude Bile

1,479
Well, the probability of a dopant being isolated would be (1-0.05)^8 (using your example). I'm sure you can figure out the rest.

Claude.