Absolutely not! You cannot take any additional credits once your AGI goes negative. Simply put - once your AGI hits $0, you then have no tax liability - therefore no need to take any other credits. You'd be eligible for a refund of any Federal taxes you had withheld during the year. You could be eligible for refundable tax credits like Earned Income Credti, Child Tax, Credit,. etc. but not a Gifts to charity deductions.