Do I mention my salary requirements or expectations?

Only unless specifically asked to. Many employers still want to see how a candidate is suited to a job rather than how the salary on offer would suit them. Some jobs, especially in the financial or sales sectors, are very results driven and as such you may well be expected to provide an estimate of your OTE or commission. This will indicate to the employer that you are both familiar with the market’s potential and the level of your ambition.