Advanced Topic 162 of 1102 Bonding & Molecular Structure
Square Planar Geometry
Four bonds and two lone pairs in an octahedral arrangement, as in XeF4.
Practise Bonding & Molecular Structure All Bonding & Molecular Structure topics
In-depth explanation of Square Planar Geometry
Square planar geometry occurs when a central atom has six electron domains, four bonds and two lone pairs, arranged octahedrally with the lone pairs placed opposite each other. The four bonded atoms lie in a single plane at 90-degree angles around the central atom. The two lone pairs point above and below that plane and cancel each other, so the molecule is nonpolar. Square planar geometry is also the typical arrangement for d8 transition metal complexes, such as many complexes of platinum(II) and nickel(II). It reflects the stability of four-coordinate d8 complexes.
Going deeper: Square Planar Geometry
Key ideas: AX4E2: XeF4, ICl4-, BrF4-, and d8 complexes: [PtCl4]2-, [Ni(CN)4]2-, [PdCl4]2-. All angles are 90 and 180 degrees. In complexes the large crystal field splitting of 4d and 5d metals favours it and gives diamagnetism. Cisplatin is cis-[Pt(NH3)2Cl2], and geometric isomers exist.
Common mistakes and connections: A common mistake is calling tetrahedral four-coordinate compounds planar, or the reverse. Nickel(II) with weak field ligands is tetrahedral and paramagnetic, but with CN- it is square planar and diamagnetic. Another error is placing the lone pairs adjacent. Links to crystal field theory, isomerism and trans effect.
Visualization of Square Planar Geometry
The two lone pairs in XeF4 sit on opposite sides of the octahedron, leaving four fluorines in a flat square around xenon. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Xenon tetrafluoride, XeF4, is square planar and nonpolar because its two lone pairs lie opposite each other.
Frequently asked questions about Square Planar Geometry
What is Square Planar Geometry?
Four bonds and two lone pairs in an octahedral arrangement, as in XeF4.
Is Square Planar Geometry a beginner, intermediate or advanced topic?
Square Planar Geometry is a advanced topic in Bonding & Molecular Structure. It builds on beginner and intermediate topics, so review those first if needed.
What should I learn before Square Planar Geometry?
Study these earlier topics in Bonding & Molecular Structure first: Trigonal Pyramidal Geometry, See-Saw Geometry, T-Shaped Geometry.
What comes after Square Planar Geometry?
The next topics in Bonding & Molecular Structure are Square Pyramidal Geometry and Bond Angle Deviations.
Can I practise Square Planar Geometry with quizzes?
Yes. The interactive lesson includes a self-check question on Square Planar Geometry, and the Bonding & Molecular Structure quiz draws on every topic in this area.
Where Square Planar Geometry fits in Bonding & Molecular Structure
Square Planar Geometry is topic 47 of 104 in Bonding & Molecular Structure.