I keep forgetting that I have a couple of 40-year-old Nikkor manual lenses that do work on my D7100 DSLR. This 105mm/2.5 would effectively be about a 155mm/2.5 on this body. It’s said that lenses this old are not optimized for digital (though this lens was renowned for sharpness back in its day).
But this ought to make an excellent portrait lens with its f2.5 max aperture. If it is a bit soft compared to modern designed-for-digital glass, so much the better.