Is the allotropy of nitrogen tetranitrogen,

if so is the only way to obtain it is to increase pressure and decrease pressure, and how long can it be maintained because online it says it can only exist for a microsecond, but if pressure and temperature is maintained why can it not be maintained longer

 

I can't find the link now, but it was a yahoo answers link.

http://en.wikipedia.org/wiki/Tetranitrogen

But I read on allotropies and it says that high pressures and change in temperatures are needed. Sadly there really is not that much information online on this subject. I couldnt even find the temperature and pressure required even that is the correct method of producing it.

My main two inquiries are if temperature and pressure is maintained would tetranitrogen still be short lived and also what temperatures and pressure is needed