Hey, Can you give us a bit more information, You are saying you want to spin the Geometry 45 degrees, Do you want to spin it only once or have it constantly spinning?
If you wish to do it only once you can do it if you look in the image you provided there is an Emitter Rotation with Roll, Pitch and Yaw, Change those to the values you want. Another way is to add a Mesh Rotation Module and give it a constant with the values you like on XYZ.
If you wish to constantly rotate it around you need a mesh rotation rate make it a constant and have in your case Y be the value you want.