Distance Between Atoms: How to Measure

[Legion81]

Is there a way to find the distance between atoms? For example, if you have a pure gold film... how can you find out how far the gold atoms are spaced?

 

[fluidistic]

I have an idea. Take a look at a periodic table of the elements and check out how much weight is worth a mole of the element you are trying to estimate its atoms distance. (Assume that your substance is free of all the other elements). Then as you know Avogadro's number, you know how many atoms there are in the "block" (or film as in your example) of the particular element (gold for you). Now it's getting a bit complex... hmm. I'm not sure it's as easy as I thought. Maybe by measuring the volume of your film it would be possible. Interesting question! I'll think on it more.

 

[Legion81]

That was the approach I first thought of, but surely there is some formula or something to just plug some numbers into... Google didn't bring up any results when I searched, so I was hoping someone knew.

Does anyone know of a table or something that has atomic distances for materials? (at X temperature, X pressure, etc.)

 

[humanino]

One way is to shine it with X-rays and look at the diffraction pattern.

 

[Legion81]

One way is to shine it with X-rays and look at the diffraction pattern.

WOW... Thanks! I bet that would work, but I was actually wondering about something on paper. I was playing around with some ideas, then I realized I had no idea how to find the distance between 2 atoms. So as you can see, an experimental value isn't really an option for me. I need a way that fits my budget... which is about a package of ramen noodles! LOL! I guess I'm out of luck.

 

[peter0302]

How about using good old fashioned chemistry (Avogadro's law, etc.)?

(Whoops, fluidistic beat me to it.

Check wikipedia. For at least some of the elements it gives you the Van der Waals radius which might be good enough for your purpuses.

 

[NoTime]

scanning tunneling microscopy is another way to do this.

Gold 100 surface -> http://en.wikipedia.org/wiki/Image:Atomic_resolution_Au100.JPG

 

[humanino]

I have to look it over, because I am not familiar with that. But I think by measuring the heat properties of your material, plus some condensed matter formalism, you should be able to determine the size of the lattice. I'm not completely positive because I don't remember all the hypothesis you need. Maybe Gokul could help us with that.

edit
Second thought, it is unlikely to work : you would probably need very high tempreatures.

 

[Legion81]

How about using good old fashioned chemistry (Avogadro's law, etc.)?

(Whoops, fluidistic beat me to it.

Check wikipedia. For at least some of the elements it gives you the Van der Waals radius which might be good enough for your purpuses.

That should work just fine. Thanks for the help!