Here's the general situation. I'm a prospective PhD student and there's this professor (say, professor X), that is very well established, is from a great institution, and works on a topic which is very appealing to me. I've sent an email a few weeks back, but I got no response.
I feel like this is natural, since this professor probably gets a lot of emails, and I'm an unknown student from another country - I don't even know if the email got through the spam filter...
I'll probably send another email (instead of a reply to the original one) in a few days, if I still don't get a reply by then. That said, already considering the possibility that there's no reply from that one, I'm left wondering:
Is it inappropriate to call a professor's office number (as displayed in their webpage and in the webpage of the department) in order to establish a first communication?
On the one hand, I feel it may be seen as a bit pushy or unprofessional, as is noted in one of the comments of this post. On the other hand, I feel it may be seen as showing persistence and determination, and I don't really have the option of going in person and knocking on the professor's door to discuss in person, as some of the locals could do.
In short, would this be something that is basically sure to black-list me, or could it actually yield a positive outcome?
Thanks in advance!