Mantra

Goddess Chandi is associated with the 9 lettered Navakshari Mantra.It is also called Navarna Mantra or Navavarna Mantra the sound body of the Great Chandika Devi composed of 9 Durgas.

Devi Atharva Sirsha Upanishad extols this mantra as

mahadananda Dayakah – the giver of the highest delight – Ananda.

This mantra is also called the Chandi Gayathri.

The mantra goes as – ‘Om – Aim Hreem Kleem Chamundayai Vitchae.

1. Om – is the Pranava Mantra represents the Nirguna Brahman. 
2. Aim – is the Vakbeeja the seed sound of Mahasaraswathi.—also the knowledge that is consciousness. – Chit. 
3. Hreem – is the Maya beeja the sound of Mahalakshmi – the all pervasive existence.. —Sat.
4. Kleem – is the Kamabeeja the seed sound of Mahakaali – the all consuming delight – the Anandaa.
5. The Chit, Sat and Anandaa gets involved in the creation in physical, vital, and mental ways – respectively as Anna – Prana and Manas. This knowledge of spiritual mysteries is represented by Chamunda Devi.

Therefore the lower creation gets evolved into higher when the Navakshari is invoked in the form of truth- Consciousness and Bliss. The being’s Maya veil is lifted when the mantra is constantly muttered by the grace of Chamunda to perceive the Eternal Truth

1. https://www.google.com/search?q=Navarna
2. https://www.google.com/search?q=Navavarna
3. https://www.google.com/search?q=Navakshari

Also See

http://www.sacred-texts.com/hin/db/bk09ch50.htm

https://www.youtube.com/results?q=Shri+Lakshmi+Kali+Saraswati+Mantra