The phrase "a complex and unprecedented" is correct and usable in written English.
It can be used to describe a situation, issue, or phenomenon that is both intricate and has not been experienced before.
Example: "The pandemic presented a complex and unprecedented challenge for healthcare systems worldwide."
Alternatives: "a complicated and unmatched" or "a multifaceted and novel".
Today's executives are dealing with a complex and unprecedented brew of social, environmental, market, and technological trends.
The statement also quoted Tony Hayward, BP's chief executive, who described the work of the previous few days as "the final step in a complex and unprecedented subsea operation".
In the present study, the gene copy number variation analysis of CCND1 in formalin fixed paraffin embedded tissue sections revealed a complex and unprecedented pattern of cellular behavior in non-muscle invasive bladder tumors.
They confirm the double-barrelled architecture, and reveal a surprisingly complex and unprecedented channel structure.
I have no personal knowledge of how it worked in the case of the federal website, but I can't imagine that it was up to the task of managing the subtle, technologically complex, and unprecedented challenge of putting together a consumer-friendly website that would seamlessly connect multiple legacy state and federal databases that were never designed to work together.
A two-selved mutant like Joe-Jim, really just a drastic version of Siamese twins, or something subtler, like one brain only more so, the pathways from one set of neurons to another fusing over time into complex and unprecedented arrangements?
In the context of complex and unprecedented issues of global change, calls for new modes of knowledge production that are better equipped to address urgent challenges of global sustainability are increasingly frequent.
Herein we describe the synthesis and crystallographic characterization of a complex possessing an unprecedented {2Fe3S μ-H)} core.
In a world that is rapidly changing, children are faced with complex challenges and unprecedented opportunities.
There will always be complex, unusual and unprecedented structures that such software cannot handle, but the task of solving more-routine synthetic questions will be taken out of the hands of researchers.
In particular, simultaneous binding of Sec17 and an SM protein to a SNARE complex is unprecedented and unexpected.
