Pay Lieu Of Notice

I have been working a private IT company and wiling to pay lieu of notice period of one month and one month service.
In appointment letter, they mentioned need two month notice or pay gross salary of two months.
But in CiteHr, many article mentioned lieu of notice will be basic salary.
Please help me to find correct way.
Do i pay gross salary or basic salary?

Notice of exit or of termination of employment and Payment in lieu of such notice, in general, is one among the conditions of the contract of employment and as such what is mentioned in that particular clause has to be complied with by the party taking recourse to it for the purpose of terminating the contract of employment. I am not aware of any rule either by way of convention of practice or by any statute categorically laying down that it shall be the basic salary alone. Deep down the concept of notice in the matter of termination of employment is to enable the other to make alternative arrangement and for the reason of situational compulsion payment in lieu thereof is envisaged.

""Do i pay gross salary or basic salary?""
What does your appointment order specify?
You have willingly accepted it while joining, so now why look to check whether it is basic pay and not gross pay??
""I have been working a private IT company and wiling to pay lieu of notice period of one month and one month service.""
Again go back to your appointment order,what does it say-as per you -2 months notice or -2 months gross pay.
If you want any change at time of exit,you have to negotiate with employer.
There is no legal way out for you.

In addition to what the seniors said above, I would like to ask whether your appointment letter defined what is salary or whether the clause on separation say that salary means basic salary only for the purpose of notice pay.If not then by going by the common interpretation what you receive every month as salary from the company without deductions for the services rendered by you will constitute salary for the purpose of notice pay.These differences need to be sorted out across the table to avoid misunderstanding and to ensure smooth exit.
B.Saikumar