The scales of Raga Amrutavarshini are as follows :
Aarohanam (Ascending) : S G3 M2 P N3 S’
Avarohanam (Descending) : S’ N3 P M2 G3 S
This raga is a Janya Raga, derived from Chitrambari (scales below), 66th on the Melakarta scale. Some musicologists consider it to be derived from Jalavarali (39th Melakarta) or Mechakalyani(65th Melakarta).
The moods associated with this raga are joy and exuberance. There are not many compositions in this raga. The ones I have heard and enjoyed are are Anandmrutakarshini by Muthuswami Dikshitar, Sarasiruha Nayane by Tyagaraja and Sudhamayi Sudhanidhi by Muthiah Bhagavatar.
Note : The 12 notes in the octave are named as below. Please note that C is used as Sa for the sake of simplicity as the scale is relative in Carnatic Music. Also note that the scales paint only a superficial picture of the raga as the gamakas(ornamentations) and prayogas (signature phrases) are a very important part of a raga.