1 of 10

# How many $Ga$ atoms are connected to one $As$ atom in solid state Gallium arsenide

Let's start straight away. In this book on page 4 Gallium arsenide's bond structure is shown like this:

$$As$$ is shown making $$5$$ covalent bonds.
Recently I came across this book. The bond structure of $$GaAs$$ is shown like this:
. Here $$As$$ is shown to make $$4$$ covalent bonds. For sure one of the above quoted images is wrong. But which?

Please explain in your answer the actual bond configuration of solid state $$GaAs$$, with established reference(s). Also give experimental proof in your answer that supports your answer.