If your candidate recognizes the name in the subject line, they are more likely to open and respond to your email. So, don’t forget to thank the employee who referred you. Use a friendly but professional tone in your communication. It’s likely that your employee has expressed an interest in speaking with you, so don’t be overly formal.
You should mention the position you’re hiring for and briefly explain why you think they might be interested. Apart from having a mutual connection, point out how your candidate’s skills and experience are relevant to your job requirements. As with all candidate sourcing emails, you should indicate what the next steps are (e.g. set up a call) and provide the information your candidate might need.