Read More
Date: 24-1-2018
![]()
Date: 26-2-2019
![]()
Date: 8-1-2017
![]() |
Nucleus Penetration affect
Penetration describes the proximity of electrons in an orbital to the nucleus. Electrons that have greater penetration can get closer to the nucleus and effectively block out the charge from electrons that have less proximity.
Table 1: Effective Nuclear Charges for Selected Atoms
Atom | Sublevel | Z | Zeff |
---|---|---|---|
H | 1s | 1 | 1 |
He | 1s | 2 | 1.69 |
Li | 1s, 2s | 3 | 2.69, 1.28 |
Be | 1s, 2s | 4 | 3.68, 1.91 |
B | 1s, 2s, 2p | 5 | 4.68, 2.58, 2.42 |
F | 1s, 2s, 2p | 9 | 8.65, 5.13, 5.10 |
Na | 1s, 2s, 2p, 3s | 11 | 10.63, 6.57, 6.80, 2.51 |
Data from E. Clementi and D. L. Raimondi; The Journal of Chemical Physics 38, 2686 (1963).
Because of the effects of shielding and the different radial distributions of orbitals with the same value of n but different values of l, the different subshells are not degenerate in a multielectron atom. For a given value of n, the ns orbital is always lower in energy than the np orbitals, which are lower in energy than the nd orbitals, and so forth. As a result, some subshells with higher principal quantum numbers are actually lower in energy than subshells with a lower value of n; for example, the 4s orbital is lower in energy than the 3d orbitals for most atoms.
|
|
دخلت غرفة فنسيت ماذا تريد من داخلها.. خبير يفسر الحالة
|
|
|
|
|
ثورة طبية.. ابتكار أصغر جهاز لتنظيم ضربات القلب في العالم
|
|
|
|
|
سماحة السيد الصافي يؤكد ضرورة تعريف المجتمعات بأهمية مبادئ أهل البيت (عليهم السلام) في إيجاد حلول للمشاكل الاجتماعية
|
|
|