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Angular wave function, limitations of slater's rule

Angular wave function: 

Wave function depends upon quantum no. l, m and often referred to atomic orbital.

the shape of these orbital depends upon angle 𝟅 and ⲫ.

     
                                             Mathematical expression for angular wave function for s & p orbital is given 

orbital               Angular wave function 

s                                     (1/4π) ^1/2
                
 pz                           (3/4π) ^1/2 cos 𝟅

px                     (3/4π) ^1/2 sin 𝟅 cos 𝟅

py                      (3/4π) ^1/2 sin 𝟅 sinⲫ. 



the expression for s orbital has no.  angle dependence ,hence s orbital are speherical symmetrical. 


limitation of slater's rule   
                                        1.it is observed that slater's rule becomes less reliable for atoms of heavier elements. 

2.  s & p orbital are grouped together for calculating effective nuclear charge. 

3.while due to higher penetration s- orbital should screen more than the orbital . 

4.all electrons in shell lower than (n-1) shielded the outer electron with equal contribution(1.00)  this not seen to be true. 


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