If we define Atheism and Materialism as follows:
"Atheism: disbelief or lack of belief in the existence of God or gods." [1]
"Materialism: the theory or belief that nothing exists except matter and its movements and modifications." [2]
Can an Atheist NOT be Materialist? Or Atheism necessarily leads to Materialism?
A Materialist Atheist is able to explain the Universe's creation using Darwinism; however, how a non-Materialist Atheist can do explain the Universe's creation **without God(s)?**
Please note that the question is NOT "is there a non-Materialist Atheist ?", but also the question is how can a non-Materialist Atheist explain the Universe's creation without God(s)?
[1] https://en.oxforddictionaries.com/definition/atheism
[2] https://en.oxforddictionaries.com/definition/materialism