impure vs unguilty

impure

adj
  • Unchaste; obscene (not according to or not abiding by some system of sexual morality) 

  • Containing undesired intermixtures 

  • Unhallowed; defiled by something unholy, either physically by an objectionable substance, or morally by guilt or sin 

unguilty

adj
  • Not guilty. 

How often have the words impure and unguilty occurred in a corpus of books? (source: Google Ngram Viewer )