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Effective Nuclear Charge given Shielding Constant Calculator

Effective Nuclear Charge Formula:

\[ Z_{eff} = Z - \sigma \]

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1. What is Effective Nuclear Charge?

Definition: The Effective Nuclear Charge is the net positive charge experienced by an electron in a polyelectronic atom.

Purpose: It helps understand how strongly an electron is attracted to the nucleus, accounting for shielding by other electrons.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Z_{eff} = Z - \sigma \]

Where:

Explanation: The shielding constant represents how much the nuclear charge is reduced by intervening electrons.

3. Importance of Effective Nuclear Charge

Details: Effective nuclear charge explains periodic trends like atomic size, ionization energy, and electronegativity.

4. Using the Calculator

Tips: Enter the atomic number (must be ≥ 1) and shielding constant (must be ≥ 0). The shielding constant is typically between 0 and Z-1.

5. Frequently Asked Questions (FAQ)

Q1: What is the shielding constant?
A: The shielding constant (σ) measures how much an electron is shielded from the nucleus by other electrons.

Q2: How do I determine the shielding constant?
A: It can be calculated using Slater's rules or obtained from experimental data like NMR spectroscopy.

Q3: What's the range for effective nuclear charge?
A: Zeff ranges from just above 0 (for outer electrons) up to Z (for the 1s electron in hydrogen).

Q4: Why does effective nuclear charge increase across a period?
A: While Z increases, shielding increases more slowly, so Zeff increases left to right.

Q5: How does effective nuclear charge affect atomic radius?
A: Higher Zeff pulls electrons closer, decreasing atomic radius.

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