Ulip & Tax Rebate?

As far as i know in yearly premium I can invest up to 100000 which will be deducted from my income but in single premium policy I will get rebate up to 20% of capital sum assured means if I invest 100000 I will get rebate on 20000 only, am I right?
The question is in single premium policy if I invest 100000 and if it is without risk cover policy will I get the tax rebate?