How do you find out the coordination number of a crystal?
For example im given a picture of the crystal structure of lithium sulfide Li2S.
SO i need to find coordination number for:
Li^+
S^2-
lithium i got right is 4 but the sulfide it says when counting sulfide: keeping in mind that another unit cell will be present above this one, so 4 for sulfide is wrong
lolz, you must a chma11 student at utsc. you are doing a great job for other 799 kids taking this course. keep it up. lol me stuck on the same question.
To find the coordination number of a crystal, you need to determine the number of atoms or ions surrounding a central atom or ion.
In the case of the crystal structure of lithium sulfide (Li2S), you are looking to find the coordination number for the Li+ and S2- ions.
Here's how you can find the coordination numbers:
1. Identify the central atom or ion: In this case, for Li+, you are looking for the number of Li+ ions surrounding it. For S2-, you are looking for the number of S2- ions surrounding it.
2. Locate the central atom or ion in the crystal structure: Find the position of the Li+ and S2- ions in the crystal lattice.
3. Determine the number of atoms or ions surrounding the central atom or ion: Count the number of nearest neighboring atoms or ions around the central atom or ion. These neighboring atoms or ions should be in direct contact with the central atom or ion.
4. Count the coordination number: The coordination number is the number of nearest neighboring atoms or ions. For example, if you count 6 neighboring atoms or ions around the central atom or ion, then the coordination number would be 6.
For lithium sulfide (Li2S):
- The coordination number for Li+ would be the number of nearest-neighbor S2- ions around each Li+ ion.
- The coordination number for S2- would be the number of nearest-neighbor Li+ ions around each S2- ion.
To determine the coordination numbers for Li+ and S2- in Li2S, examine the crystal structure, locate the Li+ and S2- ions, and count the number of nearest neighbors for each ion. By doing this, you will be able to find the coordination numbers for both Li+ and S2-.