Science, Tech, Math › Science Geometry of Diatomic Molecules Share Flipboard Email Print ThoughtCo / Ben Mills Science Chemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Biochemistry Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated January 25, 2019 Many molecules are diatomic, meaning they consist of two elements. Diatomic molecules all have the same shape or geometry. Here's a look at what this geometry is and why all diatomic molecules are the same in this regard. All diatomic molecules are linear. It doesn't matter whether they are diatomic elements or heteronuclear diatomic molecules. Diatomic molecules have to assume linear geometry because the only way to connect two points is with a line. The nuclei of the atoms are repelled by each other, so they tend to push each other away, even as the electrons are being shared. There is characteristic vibration in the resulting bond, which can be observed using lab techniques, such as spectroscopy.