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How many Ga atoms are connected to one As atom in solid state Galliumgallium arsenide?

Let's start straight away. In this book on page 4 Gallium arsenide's bondBoylestad and Nashelsky's Electronic Devices and Circuit Theory, the structure of GaAs is shown like thisas follows:
image 1
$\ce{As}$

GaAs structure, 1

Arsenic is shown making $5$five covalent bonds to neighbouring gallium atoms.
Recently

However, I came across this book. The bond structure ofrecently also saw an alternative depiction in $\ce{GaAs}$ is shown like thisRazeghi's Fundamentals of Solid State Engineering:
image 2.

GaAs structure, 1

Here $\ce{As}$, arsenic is shown to make $4$making four covalent bonds. For sure one of the above quoted images is wrong to neighbouring gallium. But which?

To how many $\ce{Ga}$ atoms one $\ce{As}$ atom is connected? Actually. Please explain your answer with established reference(s) and also give experimental proof in your answer that supports your answer.

Edit: From the present answers it appears that $As$ makes four covalent bonds, So Which source is correct? Please give appropriate references or experimental proof.

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:
image 1
$\ce{As}$ is shown making $5$ covalent bonds.
Recently I came across this book. The bond structure of $\ce{GaAs}$ is shown like this:
image 2.

Here $\ce{As}$ is shown to make $4$ covalent bonds. For sure one of the above quoted images is wrong. But which?

To how many $\ce{Ga}$ atoms one $\ce{As}$ atom is connected? Actually. Please explain your answer with established reference(s) and also give experimental proof in your answer that supports your answer.

Edit: From the present answers it appears that $As$ makes four covalent bonds, So

How many Ga atoms are connected to one As atom in solid gallium arsenide?

In Boylestad and Nashelsky's Electronic Devices and Circuit Theory, the structure of GaAs is shown as follows:

GaAs structure, 1

Arsenic is shown making five covalent bonds to neighbouring gallium atoms.

However, I recently also saw an alternative depiction in Razeghi's Fundamentals of Solid State Engineering:

GaAs structure, 1

Here, arsenic is shown making four covalent bonds to neighbouring gallium.

Which source is correct? Please give appropriate references or experimental proof.

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