Quantum needles: Scientists uncover a new shape in the tiniest form of gold

Gold's atomic alchemy: Scientists at the University of Tokyo have captured the first steps of gold nanocluster formation, revealing an unexpected discovery they call "quantum needles."

These needle-like structures, built from just dozens of atoms arranged in repeating patterns of three and four, interact with near-infrared light in ways that could revolutionize medical imaging and energy conversion.

"The formation of needles with a base of a triangle of three gold atoms instead of a nearly spherical cluster is a serendipitous finding that was far beyond our imagination," explains chemistry professor Tatsuya Tsukuda, who co-authored the study.

The researchers employed an innovative approach, deliberately slowing down the growth process to freeze the clusters at their earliest formation stages. Using single-crystal X-ray diffraction, they observed gold atoms arranging themselves unevenly, growing faster in some directions than others.

This breakthrough opens a window into what scientists had long considered a "black box" of nanocluster formation, potentially allowing for customized shapes and properties rather than leaving atomic growth to chance.