Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Chemistry

Crystal Field Theory Basics

Quick fact

The color of many transition metal complexes, such as the ruby red of chromium in corundum, comes from the absorption of specific wavelengths of light that cause electrons to jump between split d-orbitals.

Why this is interesting

You've probably seen vivid colors in gemstones or solutions, like the deep blue of a copper complex. But why do these seemingly simple compounds display such a rainbow of hues?