Maha Lakshmi is the Goddess of money and prosperity, it names Lakshmi represents Aim (Lakshya). So Lakshmi mantra is chanted in order to get achieve your aim or goal. Maha Lakshmi mantra also provides intelligent and knowledge to our mind. Here is the mantra:
"ॐ श्रीं ह्रीं क्लीं त्रिभुवन महालक्ष्म्यै अस्मांक दारिद्र्य नाशय प्रचुर धन देहि देहि क्लीं ह्रीं श्रीं ॐ ।"
"ॐ श्रीं ह्रीं क्लीं त्रिभुवन महालक्ष्म्यै अस्मांक दारिद्र्य नाशय प्रचुर धन देहि देहि क्लीं ह्रीं श्रीं ॐ ।"