Atomic Structure of a Fluorescent Ag₈ Cluster Templated by a Multistranded DNA Scaffold

Multinuclear silver clusters encapsulated by DNA exhibit size-tunable emission spectra and rich photophysics, but their atomic organization is poorly understood. Herein, we describe the structure of one such hybrid chromophore, a green-emitting Ag8 cluster arranged in a Big Dipper-shape bound to the oligonucleotide A2C4. Three 3' cytosine metallo-base pairs stabilize a parallel A-form-like duplex with a 5' adenine-rich pocket, which binds a...