What happens to the energy values of d- orbitals, Chemistry

Q. What happens to the energy values of d- orbitals?

Let us see what happens to the energy values of d- orbitals under these stages. We start with the energy level diagram of a lower triplet (t2J and upper doublet (eg) in an octahedral field. Fig. When the two Trans ligands placed along pay, z-axis, are moved away the most affected orbital would be dz2. The repulsion between the orbital and the ligand will decrease, thus making it more stable compared to others. At the same time all other orbitals containing z-axis namely dxy, dyz will also be affected by the movement of the two ligands - along the z-axis. However, these will experience less effect than the dz2 orbital. These two orbitals will become lower in energy by equal amount but less than dz2 as indicated by different slopes in Fig.

2088_What happens to the energy values of d- orbitals.png

For eg set of orbitals, if d2 orbital lowered energy due to distortion, then dx2 -y2 must go  ~p in energy by an equal amount 40 that the net result is no change. Similarly, dxz and dyz are  lowered whereas dxy is raised in energy by such an amount that the net resultant is zero. Thus  in a distorted octahedral molecule the orbitals in order of Increasing energy or  decreasing stability are : dxz, dyz)- (degenerate), GI dxy, dz2 - y2 as shown in Fig. (113. A further distortion results in the formation of a square planar complex. Here, dz2 is lowered so much SO that it is almost equal to dxy, dyz orbitals Fig. (111). Much higher will be dxy  and the least stable or the highest in energy would be d,2 - )2. In a few rare instances dz2 falls even below d,, and d,, orbitals Fig. (IV). We realise that in case of a square planar complex we shall not be able to calculate quantitatively the energy values of the orbitals in terms of crystal field splitting parameter (4). The actual values have. However, been calculated; based on these values we can calculate CFSE as well as the magnetic moment for any particular complex. It has been observed that at least the first row transition elements show greater tendency to form square planar rather than tetrahedral complexes. These observations are in line with the CFSE calculations for the two geometries.

We have thus come to the stage where we can appreciate that a simple electrostatic approach can lead to many useful results and these results are pretty close to the experimental values.  We do not expect to get perfect results since our assumptions so far are imperfect. We are, thus, left with two choices either to discard the theory completely and look for a new approach or to modify it in such way so as to account for the observed discrepancies.

Posted Date: 7/11/2013 2:48:42 AM | Location : United States

Related Discussions:- What happens to the energy values of d- orbitals, Assignment Help, Ask Question on What happens to the energy values of d- orbitals, Get Answer, Expert's Help, What happens to the energy values of d- orbitals Discussions

Write discussion on What happens to the energy values of d- orbitals
Your posts are moderated
Related Questions
cis-2-butene is a symmetrical alkene Because cis-2-butene is a symmetrical alkene, it reacts to give the similar product in either oxymercuration- reduction or hydroboration-ox

What is inductomeric effect explain .

Pig iron is cast iron with a very high carbon content: 4% by weight or more. Cast iron has at least 2% carbon by weight. Less than that, and it''s steel. Cast iron and pig iron are

what is the empirical formula of a compound that contains 53.73% iron and 46.27% sulphur?

what is the working principle of potentiometry

When beryllium is bombarded with  α -particles, extremely penetrating radiations which cannot be deflected by electrical or magnetic field are given out. These are: (1) A beam

What are different applications in which piezoelectricity is used Applications- Piezoelectric materials serve as a source of ultrasonic waves. At sea, they may be used to mea

a sample of CaCo3 and MgCo3 weighing 192g is ignited to constanr weight of 104 gm . what is the composition of mixture ?

Explain experimental evidence to demonstrate the existence of ferromagnetic domains. Temperature increases, thermal motion, or entropy, competes with ferromagnetic tendency for