Can companies force employees to serve notice period ?

Can companies force employees to serve notice period and hold experience letter even if I am ready to Pay 3 months salary without Accepting 3 months salary ?
Here Experience letter is Important thing.

Dear friend,
When you joined the company, it must have issued you the appointment letter. In the clause about separation, please check whether any conditions are mentioned about notice period and acceptance of pay in lieu of that. Many companies though accept the payment in lieu of notice period, they also introduce a clause stating that administration reserves the right to do so.
Companies include clause of notice period in the appointment letter, because sudden exit of the employee could bring discontinuity or even disruptions in the operations. Notice period is a transit period or buffer period during which company can arrange the replacement of the exiting employee. Now if the employees show willingness to pay in lieu of notice period then the very rationale behind the notice period could get defeated. Hence your company could be refusing to accept payment in lieu of the notice period.
Thanks,
Dinesh Divekar

In principle, company's cannot decline your request to pay in lieu of serving the notice period. It is clearly this or that....As a case in point, all company's ask employee's to leave by paying them notice period - when they want them to go or when they are laying off. The law is equitable and any condition in the employment contract must work both ways.
Be nice and continue to discuss with your manager, HRM, etc., you don't want to burn bridges and get a bad reference from them in the future.