How to set different themes for multiple domains
I got an solution that my colleague suggested through a contrib module.
But, not yet used it perfectly for themes.

Steps for getting it are as follows -
1. go to 


  www.github.com
  and sign up for free.
  2. Take a git clone of the 
  https://github.com/agentrickard/domain.git
  in modules folder in your drupal code base.
  3. Extend the module and try it out.