"essential to explain" is a correct and usable phrase in written English.
It typically means something is necessary in order to make the explanation understandable or clear. For example: "The inclusion of background information is essential to explain the context of the story."
Barack's leadership is essential to explain to the world what is needed.
It is absolutely essential to explain what is driving these young French people to take up arms against other young French people".
Instead, the film always coyly insists on his character's semi-decent side – essential to explain why our heroine Marlena has stayed with him – and so Waltz winds up having to pull most punches.
This addition to the model is essential to explain several effects.
A structural characterization of multi-component cellular assemblies is essential to explain the mechanisms governing biological function.
The dynamic exchange between ground and excited states of signaling proteins is essential to explain auto-inhibition and allosteric activation.
Thus, understanding those maps, even though they are sometimes wildly inaccurate, is essential to explaining people's behavior.
Through systematic approaches to morphological manipulation, it has become evident that a fundamental understanding of PEM morphology and the corresponding relationship with transport and mechanical properties is essential to explaining, predicting, and tailoring membrane performance.
The standard filters (call rate, MAF and HWE) used in the database with QC seem to delete markers essential to explaining the phenotype PTA milk.
The most important of which are essential to convincingly explain the links between altered tra expression, altered pheromone production, and behavior.
Attitudinal factors are essential in order to explain the possible bias of the endogenous relationship between car ownership and mode preferences.
