We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is Molecular Geometry?

By R. Bargar
Updated Feb 09, 2024
Our promise to you
AllTheScience is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At AllTheScience, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Molecular geometry is a term describing the three-dimensional shape of a molecule, given the number of lone pairs and bonded atoms surrounding a central atom. Any lone pairs — unbonded pairs of electrons — are used when determining the electron-pair geometry and must be considered in the shape of the molecule due to their repulsive action on the bonded pairs of electrons. This repulsion between electrons is what affects the angles between the bonded atoms and any lone pairs surrounding the central atom. These angles, rather than the number of atoms attached to the central atom, define the molecular geometry of covalently bonded molecules. Charts comparing the electron-pair geometry and molecular geometry are commonly used to show the effects of lone pairs on the shape of the molecule, as molecules with no lone pairs have the same molecular and electron-pair geometry.

A simple theory of how electrons behave is used when predicting the shape of a molecule. The theory of Valence Shell Electron Pair Repulsion (VSEPR) states that bonded and lone pairs of valence electrons will position themselves as far apart from each other as they possibly can. Utilizing this theory, the geometric shape of simple molecular compounds can be accurately determined. Other methods, such as x-ray crystallography, are needed when describing the shape of complex organic molecules including genetic material and proteins.

The simplest molecule has one central atom with two additional atoms bonded to it. According to the VSEPR theory, the two bonded atoms will position themselves as far apart from each other as possible, resulting in a linear molecular shape. The angles between the bonds are 180 degrees. Covalently bonded molecules with three atoms surrounding a central atom and no lone pairs have a trigonal planar shape. This molecule has angles of 120 degrees between the three attached atoms and lies flat in a single plane.

In order to position each bonded atom as far apart as possible, a molecule with four atoms surrounding a central atom and no lone pairs has a tetrahedral shape. Each bond angle is 109.5 degrees, forming a tetrahedron with the central atom on the inside. In this same manner, with each additional atom bonded to the central atom, the shape changes as the bonded atoms push away from each other. With the presence of lone pairs, the molecular geometry of the atom changes, as the lone pair also exerts repulsion. A molecule with three atoms and one lone pair surrounding a central atom will have a trigonal pyramidal shape, with the central atom at the top of the pyramid and the three attached atoms pushed by the lone pair into a position below the central atom.

AllTheScience is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

AllTheScience, in your inbox

Our latest articles, guides, and more, delivered daily.

AllTheScience, in your inbox

Our latest articles, guides, and more, delivered daily.