What is the meaning and application of this new chemistry formula?

[maxpayne_lhp]

Well, hello!
I was informed a new formula. As a non-native, I can't give out the definitons, I hope that you can help me call some.
Well, here is the formula:
\Delta=\frac{2+\Sigma n_i (V_i-2)}{2}
Well, as far as I can say, \Delta here is equal to the total of the linkage C=C+ number of 'cycles' in my language?
So, what is this for and how was it formed? I really want to know so that I can apply to my problems.
Thanks for your time and help!

 

[maxpayne_lhp]

Ah, by the way, We have:
If \Delta =0, the subtance is not 'full' so; it has no \pi_{cc} linkage, no 'cycle.
If \Delta =1, the subtance has 1 \pi_{cc} linkage OR 1 'cycle'
If \Delta =2, the subtace has 2 \pi_{cc} linkages OR 1 \pi_{cc} linkage + 1 'cycle' OR 2 'cycles'
So, what is this all about?
Thanks again!

 

[wais]

The formula you mentioned, \Delta=\frac{2+\Sigma n_i (V_i-2)}{2}, is actually a mathematical representation of the Euler's formula in graph theory. This formula is used to determine the number of faces in a planar graph, where \Delta represents the number of faces, n_i represents the number of vertices of degree i, and V_i represents the number of faces of degree i. In simpler terms, it helps determine the number of regions or cycles in a graph.

In chemistry, this formula can be applied in various ways. For example, it can be used to determine the number of rings or cycles in a molecule, which can provide information about the molecule's stability and reactivity. It can also be used to analyze the structure of complex molecules and predict their properties.

The formula was derived based on the concept of planar graphs and has been widely used in various fields, including chemistry. It is a useful tool for analyzing and understanding complex structures and can be applied to a variety of problems.

I hope this helps clarify the meaning and application of the formula for you. If you have any further questions, please don't hesitate to ask.