  Coupled cluster Green's function (GFCC) calculation has drawn much attention
in the recent years for targeting the molecular and material electronic
structure problems from a many body perspective in a systematically improvable
way. However, GFCC calculations on scientific computing clusters usually suffer
from expensive higher dimensional tensor contractions in the complex space,
expensive interprocess communication, and severe load imbalance, which limits
it's routine use for tackling electronic structure problems. Here we present a
numerical library prototype that is specifically designed for large scale GFCC
calculations. The design of the library is focused on a systematically optimal
computing strategy to improve its scalability and efficiency. The performance
of the library is demonstrated by the relevant profiling analysis of running
GFCC calculations on remote giant computing clusters. The capability of the
library is highlighted by computing a wide near valence band of a fullerene C60
molecule for the first time at the GFCCSD level that shows excellent agreement
with the experimental spectrum.
