why is the molecule of Li2^2- a non-existent?
this is my reasoning:
in the molecule, there is 5 bonding electrons and 3 antibonding electrons. (5-3)/2 gives a bond order of 1, which means the molecule should be diamagentic.
please help!
To determine whether the molecule Li2^2- exists or not, we need to consider the electron configuration and bond order.
The formula Li2^2- suggests that this molecule consists of two lithium atoms with a charge of 2-.
First, let's determine the electron configuration of a neutral lithium atom.
The atomic number of lithium is 3, which means it has 3 electrons. The electron configuration of a neutral lithium atom is 1s^2 2s^1.
Now, let's consider the lithium ion (Li+). When an atom loses an electron, it becomes positively charged. In the case of lithium, when it loses one electron, it forms a stable Li+ ion with a completely filled 1s^2 orbital.
Since the formula Li2^2- suggests that each lithium atom in the molecule has a charge of 2-, we can infer that each lithium atom has gained two electrons. Adding two electrons to the neutral lithium atom's electron configuration gives us 1s^2 2s^2.
Now, let's calculate the bond order of Li2^2-. The bond order is defined as half the difference between the total number of bonding and antibonding electrons.
In this case, we have 4 bonding electrons (2 from each lithium atom) and 0 antibonding electrons since all the orbitals are completely filled.
Applying the formula, (4-0)/2, we get a bond order of 2.
A bond order of 2 suggests a stable molecule. Therefore, the molecule Li2^2- does exist.
It's essential to note that the existence of a molecule also depends on other factors such as the energetics of its formation and the stability of such compounds in certain conditions.