# Ceramic Properties vs. Solid Properties

1. Aug 9, 2013

### shakystew

Hello,

Quick run-down: I am attempting to model thin film materials (e.g. Ti-Al-N) for thermal analysis. I am

confused on how to figure out the number density of Nitrogen for a ceramic. All

the tables I have in school textbooks are for gas (~0.0013 g/cm3). I can find

density of nitrogen/oxygen in a solid state, but is this the correct density?

Question: Is the density of the solid state the correct density to use for modelling ceramics? I realize

the structural differences, but not certain if the density can be estimated to be

the same.

Any assistance will be much appreciated!

2. Aug 9, 2013

### Baluncore

The cutting edge of technology.
If you know the structure, maybe you can calculate the density from the ionic radii.
Calculate also for another similar material with a known density to check the method.

3. Sep 2, 2013

### ChaseRLewis

It's pretty easy if you know the structure. If you don't then some sort of mass spec is your only hope on a real sample.

You basically need to find a repeating unit of structure then calculate the weight / volume of that repeating unit. On planar surfaces sometimes planar density is calculated as weight / area instead like graphene as it's thickness is pretty much non-existent.

If you have the chemical formula (which may not be consistent for a thin film if it is doped) you assume you have a repeating unit of the chemical formula calculate the percent mass of Nitrogen and multiply that by total mass/total volume. Similar to above, but easier.

Otherwise you do a mass spec of the results figure % mass nitrogen and divide by volume.