Atomic / phase data
Reference atomic and phase values are source-reviewed.
Material structure
The ordinary elemental structure is measured; the viewer is a teaching representation.
Medical/compound boundary
Clinical GBCAs are chelated compounds and are distinct from elemental Gd and iodinated contrast.
Element vs material uses
Uses distinguish elemental metal from compounds, alloys, dopants or medical formulations.
Geography
Discovery/supply context is selective and does not fabricate deposits or facilities.
The lens describes evidence status, not confidence theatre. “Unknown” is kept unknown, and teaching schematics are not presented as direct measurements.
Gadolinium (Gd)
Gadolinium is element 64, a lanthanide with seven 4f electrons, strong magnetic behavior and exceptional neutron-capture isotopes. Its chemistry also underpins gadolinium-based MRI contrast agents—but those chelated compounds are not elemental Gd metal.
Gadolinium atomic number, mass, electron configuration and key properties
Gadolinium: quick answers
How many protons, neutrons and electrons does gadolinium have?
Gadolinium’s atomic number is 64, so every gadolinium atom has 64 protons, and a neutral atom also has 64 electrons. Its most common natural isotope, gadolinium-158, has 94 neutrons (other isotopes have different neutron counts).
What is the symbol for gadolinium?
The chemical symbol for gadolinium is Gd.
Is gadolinium a solid, liquid or gas at room temperature?
Gadolinium is a solid at room temperature (about 25 °C).
What family (group) is gadolinium in?
Gadolinium is a lanthanide, in period 6 (the f-block row shown below the main table) of the periodic table.
What is the electron configuration of gadolinium?
The ground-state electron configuration of gadolinium is [Xe] 4f⁷ 5d¹ 6s².
From atomic number to chemistry
Read these as a chain of causes, not as isolated facts. Each step links to the concept hub if you want the underlying idea explained.
64 protons define gadolinium.
The ground-state configuration frames atomic and chemical behavior.
Periodic position organizes recurring chemistry and trends.
The teaching nucleus is one isotope, not the relative atomic mass.
Phase claims preserve source-reviewed evidence and allotrope context.
Gadolinium in its period and family
Gadolinium follows europium in the lanthanide series. Gd³⁺ retains the particularly stable half-filled 4f⁷ shell, producing large magnetic moments and distinctive neutron/magnetic behavior.
Gadolinium Visual Lab
Explore Gd across the teaching nucleus, isolated-atom orbitals, evidence-aware material structure and temperature/evidence views, then connect those models to uses, isotopes, search-led questions and source-backed context.
Every mark points to one exact feature
The numbered markers explain the same information system used throughout Element Lookup. Unknown or predicted fields remain visibly labelled rather than being replaced with guesses.
Gadolinium in one minute
Atomic number 64 means 64 protons.
Neutral Gadolinium has [Xe] 4f⁷ 5d¹ 6s².
Its representative teaching isotope is ¹⁵⁸Gd.
Elemental gadolinium, gadolinium compounds and gadolinium-based contrast agents (GBCAs) must be kept separate.
The ordinary material reference is hcp near room temperature; bcc at high temperature.
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 18 · 25 · 9 · 2 electrons
The 4f_xyz, 5d_z2, 6s visuals are isolated-atom probability teaching models. They do not depict electron bands, bonding orbitals or the crystal electronic structure of Gadolinium materials.
Gadolinium metal is HCP near room temperature and transforms to BCC at high temperature shortly before melting. The viewer shows the ordinary HCP lattice; the phase track carries the high-temperature transition.. The viewer is evidence-aware: measured structures are identified as such; unknown bulk structures stay unknown.
Teaching visualization; not a literal finite sample or thermal trajectory.What this model does—and does not—show
The 4f_xyz, 5d_z2, 6s visuals are isolated-atom probability teaching models. They do not depict electron bands, bonding orbitals or the crystal electronic structure of Gadolinium materials.
Where do I meet gadolinium?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
Magnetism
Gadolinium’s half-filled 4f shell gives strong magnetic moments and a magnetic ordering transition near room temperature.
4f⁷ → large moment → neutron/MRI materials
Elemental gadolinium, gadolinium compounds and gadolinium-based contrast agents (GBCAs) must be kept separate. GBCAs are chelated gadolinium compounds used in MRI and are distinct from iodinated X-ray/CT contrast agents. Medical safety depends on the specific agent and patient factors.
Gd³⁺ 4f⁷
Gd³⁺ retains a half-filled 4f shell and a large magnetic moment.
Gadolinium in periodic context
Compare nearby or family-related elements without treating a trend as a substitute for element-specific evidence.
| 4f | near half-filled |
|---|---|
| States | +2/+3 |
| 4f | half-filled Gd³⁺ |
|---|---|
| Magnetism | strong |
| Series | lanthanide |
|---|---|
| Period | 6 |
Gadolinium properties: atomic, physical, thermal and chemical
Categories follow the science of this element rather than a fixed decorative template. Each row carries condition/provenance context and an evidence label; unknown values stay unknown.
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Atomic number | 64 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 157.25 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Xe] 4f⁷ 5d¹ 6s² | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group Lanthanide · Period 6 · f-block | Periodic-table placement | Evaluated |
| Electronegativity | 1.20 | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ¹⁵⁸Gd | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Silvery lanthanide metal | Source-reviewed; see Sources below | Evaluated |
| Density | 7.90 g/cm³ | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | HCP near room temperature; BCC at high temperature | Gadolinium metal is HCP near room temperature and transforms to BCC at high temperature shortly before melting. The viewer shows the ordinary HCP lattice; the phase track carries the high-temperature transition. | Measured |
| Classification | Lanthanide | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | Gadolinium metal is HCP near room temperature and transforms to BCC at high temperature shortly before melting. The viewer shows the ordinary HCP lattice; the phase track carries the high-temperature transition. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 1586 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 3546 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | At approximately standard pressure, gadolinium is HCP through most of its solid range, changes to BCC near 1534 K, melts near 1586 K, and boils near 3546 K. | Shared phase registry drives the slider, regions and markers. | Evaluated |
| Condition warning | Temperature and pressure define phase behavior; purity/allotropy may matter. | Teaching condition statement | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Common oxidation states | +3 | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | Gd³⁺ | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Gadolinium follows europium in the lanthanide series. Gd³⁺ retains the particularly stable half-filled 4f⁷ shell, producing large magnetic moments and distinctive neutron/magnetic behavior. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ¹⁵⁸Gd | Stable natural isotope | Most abundant natural gadolinium isotope. | Evaluated |
| ¹⁵⁷Gd | Stable natural isotope | Notable for an exceptionally large thermal-neutron capture cross section. | Evaluated |
| ¹⁵²Gd | Very long-lived natural isotope | Radioactive only on immense timescales. | Evaluated |
| Teaching nucleus | ¹⁵⁸Gd · 64 protons + 94 neutrons | Reference isotope used in the nucleus model | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Page evidence note | Atomic identity, reference values and ordinary structures are source-reviewed. Material viewers are teaching representations, not crystallographic refinements. Search demand never overrides measured/evaluated evidence or compound-vs-element distinctions. | Evidence summary for this guide | Reviewed |
| Structure evidence | Gadolinium metal is HCP near room temperature and transforms to BCC at high temperature shortly before melting. The viewer shows the ordinary HCP lattice; the phase track carries the high-temperature transition. | Measured structure, labelled schematic, prediction or explicit unknown as applicable. | Reviewed |
| Map evidence rule | Real pins are reviewed examples; conceptual layers are used when pins would mislead. | Geography Explorer 2.0 | Reviewed |
| Source set | 3 primary/reference links listed below | Open the Sources section for the actual references. | Reviewed |
Is Gadolinium a solid, liquid or gas? State at temperature
At approximately standard pressure, gadolinium is HCP through most of its solid range, changes to BCC near 1534 K, melts near 1586 K, and boils near 3546 K.
Where on Earth is Gadolinium found or produced?
Who discovered Gadolinium, and when?
Jean Charles Galissard de Marignac observed spectral evidence for a new rare-earth component.
Paul-Émile Lecoq de Boisbaudran isolated gadolinium oxide more clearly and the element became established.
Gadolinium was named after Johan Gadolin, a pioneer of rare-earth chemistry.
Gd compounds became important in magnetic, neutron, optical and MRI-contrast technologies.
From source material to Gadolinium applications: high-level material path
Gadolinium is separated from mixed rare-earth mineral concentrates through industrial rare-earth refining.
Purified compounds feed magnetic, neutron, scintillator and medical-contrast manufacturing chains.
MRI contrast products use strongly chelated gadolinium compounds under pharmaceutical quality systems; they are not elemental-metal formulations.
Recycling/recovery opportunities vary by material system; no pharmaceutical or chemical preparation instructions are provided.
What is gadolinium used for?
MRI contrast agents
Chelated gadolinium compounds are used in selected MRI examinations under medical regulation.
Neutron absorption
Gd-containing materials exploit very strong neutron-capture isotopes.
Magnetic materials
Gadolinium supports magnetocaloric and magnetic-material research.
Scintillators & phosphors
Gd compounds occur in detector, phosphor and ceramic host materials.
Gadolinium isotopes and natural abundance
¹⁵⁸Gd
Stable natural isotopeMost abundant natural gadolinium isotope.
¹⁵⁷Gd
Stable natural isotopeNotable for an exceptionally large thermal-neutron capture cross section.
¹⁵²Gd
Very long-lived natural isotopeRadioactive only on immense timescales.
Five-question Gadolinium check
What is Gadolinium’s atomic number?
Which classification best fits Gadolinium?
What is the representative teaching isotope?
Which statement respects the material evidence?
Which rule should guide real-world uses?
Gadolinium questions students commonly ask
Each answer starts with the direct fact, then explains the chemistry, evidence or material context so the result is understandable rather than merely memorized.
What is gadolinium?
Short answer: Gadolinium is chemical element 64, a lanthanide metal.
Atomic number 64 means every gadolinium nucleus contains 64 protons. In the periodic table, Gadolinium is classified here as a lanthanide in Period 6 and Group Lanthanide. Gadolinium follows europium in the lanthanide series. Gd³⁺ retains the particularly stable half-filled 4f⁷ shell, producing large magnetic moments and distinctive neutron/magnetic behavior.
Key point: Gd is element 64; its periodic position and electron structure explain the rest of the page.
Is gadolinium a metal?
Short answer: Yes. Elemental gadolinium is a silvery lanthanide metal.
This guide classifies Gadolinium as a lanthanide. Its periodic position is Period 6, f-block, Group Lanthanide. Gadolinium follows europium in the lanthanide series. Gd³⁺ retains the particularly stable half-filled 4f⁷ shell, producing large magnetic moments and distinctive neutron/magnetic behavior.
Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.
What is gadolinium used for?
Short answer: Gadolinium compounds are used in MRI contrast agents, neutron-absorbing materials, scintillators and magnetic-material research.
MRI contrast agents: Chelated gadolinium compounds are used in selected MRI examinations under medical regulation. Neutron absorption: Gd-containing materials exploit very strong neutron-capture isotopes. Elemental gadolinium, gadolinium compounds and gadolinium-based contrast agents (GBCAs) must be kept separate. GBCAs are chelated gadolinium compounds used in MRI and are distinct from iodinated X-ray/CT contrast agents. Medical safety depends on the specific agent and patient factors.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
Does gadolinium contain iodine?
Short answer: No. Gadolinium is element 64. Gadolinium-based MRI contrast agents are chemically distinct from iodinated X-ray/CT contrast agents.
Elemental gadolinium, gadolinium compounds and gadolinium-based contrast agents (GBCAs) must be kept separate. GBCAs are chelated gadolinium compounds used in MRI and are distinct from iodinated X-ray/CT contrast agents. Medical safety depends on the specific agent and patient factors. Elemental gadolinium, gadolinium compounds and gadolinium-based contrast agents (GBCAs) must be kept separate.
Key point: Use the direct answer together with the material, isotope and evidence context shown elsewhere on the page.
Is gadolinium contrast safe?
Short answer: Approved GBCAs have established benefits and known risks, including retention and special kidney-related cautions. The appropriate agent and risk assessment are medical decisions for qualified clinicians.
Elemental gadolinium is not an MRI contrast injection. Questions about GBCA choice, kidney function, pregnancy, prior reactions, retention or individual medical risk require a qualified clinician and the product-specific prescribing information.
Key point: Safety claims must be substance- and exposure-specific.
Where is gadolinium found?
Short answer: It occurs mixed with other rare-earth elements in minerals and is separated during rare-earth processing.
Gadolinium is separated from mixed rare-earth mineral concentrates through industrial rare-earth refining. The Geography Explorer keeps natural occurrence separate from resources, industrial production and recycling, because those datasets answer different questions about gadolinium.
Key point: Natural occurrence, resources, production and recycling are different geography questions.
Who discovered gadolinium?
Short answer: Spectral evidence was reported by de Marignac in 1880; later isolation work helped establish the element.
In 1880, Jean Charles Galissard de Marignac observed spectral evidence for a new rare-earth component. In 1886, Paul-Émile Lecoq de Boisbaudran isolated gadolinium oxide more clearly and the element became established.
Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.
Scientific sources for Gadolinium
- Royal Society of Chemistry - Gadolinium
- FDA - Gadolinium-based contrast agent safety communications
- NIST - Atomic Weights and Isotopic Compositions
Questions to ask next about Gadolinium
A good element lesson should lead to the next useful question, not end after a list of facts.
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