This function returns a 4-column array of chiral indices [n, m, diameter (in nm), metallicity (metal = 1, semiconducting = 0)] which closely match an input carbon nanotube diameter, d. Additionally, it will filter out chiralities if you specify whether the tube should be metallic, semiconducting or both. The user can also specify the range of valid diameters to choose from (default is d +/- 0.1 nm).

Duplicate chiralities (e.g. (6,5) and (5,6)) are discarded so only one unique chirality remains in the list.

The function declaration is:
chiralIndices = findCNTChiralIndices(d,findMetallic,deltad).

findMetallic is an input to tell the program to find metallic (=1), semiconducting (=0), or both (=-1, default).

Examples:
1. Find chiral indices that fit in a diameter range of 0.7 +/- 0.1 nm.

>> chiralIndices = findCNTChiralIndices(0.7)

chiralIndices =

4 5 0.6116 0
3 6 0.6215 1
0 8 0.6264 0
2 7 0.6409 0
1 8 0.6690 0
5 5 0.6781 1
4 6 0.6826 0
3 7 0.6960 0
0 9 0.7047 1
2 8 0.7177 1
1 9 0.7470 0
5 6 0.7470 0
4 7 0.7551 1
3 8 0.7712 0
0 10 0.7830 0
2 9 0.7947 0

2. Find chiral indices of metallic tubes in a diameter range 1.5 +/- 0.02 nm.

>> chiralIndices = findCNTChiralIndices(1.5,0,0.02)

chiralIndices =

0 19 1.4878 0
5 16 1.4878 0
2 18 1.4939 0
10 12 1.4939 0
9 13 1.5001 0
4 17 1.5123 0