Most elements on the periodic table are paramagnetic, meaning they have at least one unpaired electron that gives them a net magnetic moment. The largest groups are the transition metals, the lanthanides (rare earth elements), and several actinides. In total, roughly 35 elements are paramagnetic in their standard, elemental state.
Why Unpaired Electrons Matter
Every electron spins, and that spin creates a tiny magnetic field. When electrons are paired in the same orbital, their spins point in opposite directions and their magnetic fields cancel out. An atom with all paired electrons has no net magnetic moment and is diamagnetic, meaning it is very slightly repelled by a magnetic field.
An atom with one or more unpaired electrons, on the other hand, has a leftover magnetic moment. Place that atom in an external magnetic field and the unpaired electrons’ moments tend to align with it, pulling the material toward the field. That attraction is paramagnetism. It’s weaker than the permanent magnetism you see in a refrigerator magnet (ferromagnetism), and it disappears the moment you remove the external field because thermal energy quickly scrambles the alignment.
The Full List of Paramagnetic Elements
The elements that are paramagnetic in their standard elemental form span several regions of the periodic table:
- First-row transition metals: Scandium, titanium, vanadium, manganese (chromium is antiferromagnetic; iron, cobalt, and nickel are ferromagnetic; copper is diamagnetic)
- Second-row transition metals: Yttrium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, silver
- Third-row transition metals: Hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum
- Lanthanides: Lanthanum, cerium, praseodymium, neodymium, samarium, europium, terbium, dysprosium, holmium, erbium, thulium, ytterbium
- Actinides: Thorium, protactinium, uranium, plutonium
A few patterns stand out. Transition metals dominate the list because their partially filled d orbitals almost always contain unpaired electrons. The lanthanides are even more strongly paramagnetic in many cases because their partially filled f orbitals can hold up to seven unpaired electrons, producing very large magnetic moments.
Transition Metals: The Biggest Group
Transition metals have between one and five d electrons available to be unpaired, depending on the element and its electron configuration. Manganese, for instance, has five unpaired d electrons in its ground state, giving it a particularly strong paramagnetic response. Titanium and vanadium have two and three unpaired d electrons, respectively.
Not every transition metal is paramagnetic, though. Iron, cobalt, and nickel are ferromagnetic: their unpaired electrons don’t just align individually in a field but spontaneously align with each other in large domains, creating permanent magnets. Copper and zinc are diamagnetic because their d orbitals are completely filled. Gold is also diamagnetic for the same reason.
Lanthanides: The Strongest Paramagnets
The lanthanide series, from lanthanum through ytterbium, includes some of the most strongly paramagnetic elements. Their f orbitals can accommodate up to 14 electrons across seven sub-orbitals. In gadolinium, for example, seven unpaired f electrons produce a magnetic moment so large that it sits right on the boundary between paramagnetism and ferromagnetism (gadolinium is actually ferromagnetic below room temperature).
This strong paramagnetism has a well-known medical application. Gadolinium-based compounds are injected as contrast agents during MRI scans. The seven unpaired electrons disturb the magnetic behavior of nearby water molecules in your body, which changes the signal the MRI scanner picks up and makes organs, blood vessels, and abnormal tissues easier to see on the resulting images.
Oxygen: A Surprising Paramagnetic Molecule
Elements aren’t the only paramagnetic substances. Molecular oxygen (O₂) is paramagnetic even though it has an even number of electrons. This puzzled chemists for decades until molecular orbital theory explained it: when two oxygen atoms bond, two electrons end up in separate high-energy orbitals rather than pairing up in one. Those two unpaired electrons make liquid oxygen weakly magnetic, something you can actually demonstrate by pouring it between the poles of a strong magnet and watching it cling there.
Paramagnetism vs. Ferromagnetism vs. Diamagnetism
These three types of magnetism differ in strength, direction, and what happens when the external field goes away.
- Diamagnetic materials have all paired electrons, produce a tiny magnetic field that opposes the external field, and lose even that weak effect the instant the field is removed. Examples: copper, gold, bismuth, water.
- Paramagnetic materials have unpaired electrons that align with the external field, creating a small positive attraction. Remove the field, and thermal motion destroys the alignment within moments. Examples: aluminum, platinum, tungsten, oxygen.
- Ferromagnetic materials have unpaired electrons that spontaneously align in large domains, producing strong magnetism that can persist after the field is removed. Only three elements are ferromagnetic at room temperature: iron, cobalt, and nickel.
The strength difference is dramatic. Ferromagnetic materials can have magnetic responses up to 10,000 times greater than paramagnetic ones. Paramagnetic attraction, while measurable, is too weak to feel with your hands.
Temperature and Paramagnetic Strength
Paramagnetism gets weaker as temperature rises. This relationship, known as Curie’s law, says that a paramagnetic material’s magnetic susceptibility is inversely proportional to its absolute temperature. At higher temperatures, atoms vibrate more aggressively, disrupting the alignment of magnetic moments with the external field. Cool the material down and the paramagnetic response strengthens because there’s less thermal energy fighting the alignment.
This is also why some elements cross the line between paramagnetism and ferromagnetism at specific temperatures. Gadolinium, for example, becomes ferromagnetic below about 20°C. Above that temperature, thermal energy prevents the large-scale domain alignment that ferromagnetism requires, and the element behaves as a paramagnet instead.