Render issues with eevee 2.81: white square *** solved ***

Hello everyone, I am working on a shockwave using particles and a smoke domain. I have added materials, turned the smoke green and when I press on F12 all I get is a completely white square. I haven’t added material for the particle system yet. Am testing the rendering at this point. Am including what the render viewport sees, the rendered image and finally the blend file through dropbox as it is too large for the forum. Been at it for hours and can’t correct this. Can someone point me in the right direction please? Thanks


*** Finally figured it out: had to activate “clamp” in the math node. Go figure! ***

Blend file here: