Filing Taxes

My spouse and I have been separated for 8 months with no SA in place. He is currently unavailable and will most likely be so for several months. I have all our documents needed for filing taxes and am considering filing separately to make next year a completely clean break. Since we have separated, he has provided no financial support at all (there are children involved). If I opt to file taxes separately can I claim the children as my exemptions since I provided all of their support for the last 6 months of 2011 and 50+% for the first 6 months of 2011?
Thank you.

If you are the custodial parent and there is no agreement, or court order, to the contrary then you may claim them on your income taxes, but if you both claim them it will trigger an audit.