What is the Difference Between Covalent Radius and Metallic Radius?

The main difference between covalent radius and metallic radius lies in the types of bonding and the structures they describe.

Covalent Radius: This is half the distance between the centers of two homonuclear (same element) atoms that are bonded together by a single covalent bond. Covalent bonding occurs between nonmetals or metalloids, where the electrons are shared between the atoms.
Metallic Radius: This is half the distance between two adjacent metal ions in a metallic structure. Metallic bonding involves the sharing of delocalized electrons among a lattice of positively charged ions, resulting in a strong cohesive force within the structure.

Some key differences between covalent radius and metallic radius include:

In a covalent bond, electrons are strongly attracted by the nuclei of the two bonded atoms, while in a metallic bond, electrons are only weakly attracted by the metal ions.
Covalent radius is applicable to nonmetals and metalloids, while metallic radius is applicable to metals.
There are no specific trends for the covalent radius of chemical elements, but the metallic radius follows trends in the periodic table, such as decreasing along a period and increasing down a group.

In summary, covalent radius refers to the distance between two atoms of the same element that are covalently bonded, while metallic radius refers to the distance between adjacent metal ions in a metallic structure. Due to the differences in bonding and structures, metallic radius is generally longer than covalent radius.

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What is the Difference Between Covalent Radius and Metallic Radius?

Comparative Table: Covalent Radius vs Metallic Radius

The main difference between covalent radius and metallic radius lies in the nature of the atomic bonds and the environment in which the atoms are found. Here is a table comparing the two concepts:

Feature	Covalent Radius	Metallic Radius
Definition	Covalent radius is half the distance between the nuclei of two single-bonded atoms.	Metallic radius is half the distance between two adjacent metal ions in a metallic structure.
Bonding Type	Represents a covalent bond, which involves the sharing of electron pairs between two nonmetal atoms.	Represents a metallic bond, which involves the sharing of electron density over a lattice structure of metal ions.
Measurement	Typically measured in picometers (pm) or angstroms (Å).	Measured in picometers (pm).
Variation	May vary depending on the nature of the chemical bond and the environment of the atoms.	Decreases along a period of the periodic table due to the increase in effective nuclear charge.
Relation	Can be determined by taking the average of bond distances between atoms in each allotrope for chemical elements having multiple allotropes.	Increases down a group in the periodic table because the principal quantum number increases, leading to larger atomic sizes.

In general, metallic radius is greater than covalent radius.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.