Reaching out after applying - who?

I'm job hunting as a new grad. There's a position that I think I'd be really great for and want to reach out to a hiring manager after applying to make sure I get noticed, but I'm unsure who is appropriate to contact. I'm applying to a large-ish company directly (not via LinkedIn or a recruiter), so it's hard to identify the right person. I’ve searched on LinkedIn, but people don’t list their departments, etc. Would it be inappropriate to message the head of Talent Acquisition, or is it better to reach out to someone more junior and hope it gets passed along? Or should I focus more on reaching out to whoever I'd be reporting to on the job? Thanks for any tips!