What is the bond angle of water?

I have been trying to find out the bond angle of $\ce{H2O}$, but every site I visit has a different answer.

So far, I have found the following angles listed:

• Site 1: 104.4º


• Site 2: 107.5º OR 104.5º, depending on where you are in the article.


• Site 3: 104.5º

Answer

In your comment, you say you are interested in "liquid water".

The values in your self-answer are for gas phase water, and the second source is citing the first source, so it is really just one source. The value is determined from gas phase rotation spectroscopy.

For liquid water, the value is not as precisely known:

105.5° (calculated) and 106° (experimental) as reported in Structural, electronic, and bonding properties of liquid water from first principles J. Chem. Phys. 111, 3572.