Solid state chemistry has produced a plethora of materials with properties not found in nature. For example, high-temperature superconductivity in copper-oxide compounds called cuprates is drastically different from the superconductivity of naturally occurring metals and alloys and is frequently referred to as unconventional. Unconventional superconductivity is also found in other synthetic compounds, such as iron-based and heavy-fermion superconductors. Physicists at Ames National Laboratory have found compelling evidence of unconventional superconductivity in synthetic samples of Rh17S15, which is also found in nature as the mineral miassite.
Superconductivity is when a material can conduct electricity without energy loss.
Superconductors have applications including medical MRI machines, power cables, and quantum computers.
Conventional superconductors are well understood but have low critical temperatures.
The critical temperature is the highest temperature at which a material acts as a superconductor.
In the 1980s, scientists discovered unconventional superconductors, many of which have much higher critical temperatures.
“All these materials are grown in the lab,” said Ames National Laboratory researcher Ruslan Prozorov.
“This fact has led to the general belief that unconventional superconductivity is not a natural phenomenon.”
“It is difficult to find superconductors in nature because most superconducting elements and compounds are metals and tend to react with other elements, like oxygen.”
“Miassite is an interesting mineral for several reasons, one of which is its complex chemical formula.”
“Intuitively, you think that this is something which is produced deliberately during a focused search, and it cannot possibly exist in nature. But it turns out it does.”
Growing the miassite crystals was part of a larger effort to discover compounds that combine very high melting elements (like Rh) and volatile elements (like S).
“Contrary to…
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