The Molecular Level

The Molecular Level is a main main story quest and achievement/trophy in Fallout 4.

Quick walkthrough
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 * data2=Talk to Sturges.
 * data3=Talk to Tinker Tom.|class=va-chart-body}}

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 * data2=Build the Reflector Platform.
 * data3=Build the Reflector Platform Complete the Signal Interceptor.|class=va-chart-body}}

Detailed walkthrough
Before the Sole Survivor can utilize the freshly acquired Courser chip, it needs to be analyzed by someone familiar with the Institute technology. The best person for the job happens to be Tinker Tom from The Railroad.
 * Note: If the Sole Survivor haven't encountered The Railroad yet, follow the Road to Freedom to find the hidden Railroad HQ and talk to Desdemona.

Alternatively, if the Survivor already met or is a member of the Railroad, head to Railroad HQ. Speak to Desdemona and agree to her terms. Give the Courser chip to Tinker Tom, who will crack the encryption and provide the code for the chip.
 * Note:If the Sole Survivor has killed all the members of The Railroad, travel to Goodneighbor and talk to Amari who directs the Sole Survivor to the Railroad HQ. Once there, use Tinker Tom's computer which teaches the Sole Survivor how to decrypt the Courser chip.

Return to Virgil. He will offer the plans for the teleporter in exchange for a favor: if the teleporter works, the Survivor must retrieve a serum from Virgil's old laboratory inside The Institute to cure his FEV affliction. Accept his terms and receive the plans. However, the teleporter is no simple machine. Expert help and lot of resources will be needed to construct it.

At this point, the Sole Survivor needs to make a choice to enlist the help of one of the three factions (the Minutemen, the Brotherhood of Steel or The Railroad). Speak to either Proctor Ingram (BoS), Sturges (Minutemen) or Tinker Tom (Railroad) and arrange for the construction of the teleporter. The chosen expert will travel to the building site and explain the requirements and necessary materials for each of the four components: stabilized reflector platform, beam emitter, console and relay dish.

The teleporter can be built at any owned settlement (even if picking The Railroad who suggest the Mercer Safehouse, although the crafting items they provide will still get delivered to the safehouse) Unless they chose to ally with the Brotherhood in which case it will be built at Boston Airport. Requirements for the teleporter:
 * Enough flat surface area without any obstructions (the emitter needs to be built upon the platform, the combined structure takes up a lot of space).
 * Enough "Size" allotment remaining at the settlement (the teleporter is quite large).
 * It cannot be built indoors.
 * 27 power.
 * The components have to be linked together with power cables on the same network.
 * For the stabilized reflector platform:
 * Aluminum x 10
 * Circuitry x 3
 * Steel x 5
 * For the molecular beam emitter:
 * Rubber x 2
 * Steel x 10
 * Copper x 5
 * Military-grade circuit board x 1
 * Circuitry x 3
 * For the control console:
 * Rubber x 2
 * Copper x 3
 * Steel x 5
 * Biometric scanner x 1
 * For the relay dish:
 * Copper x 3
 * Steel x 3
 * Cloth x 6
 * Gold x 3

When everything is built, linked together and supplied with enough power, the teleporter is ready for use. Talk to the expert, and get ready for the voyage. The expert (of allied faction) will instruct the Sole Survivor to step on the platform and the teleportation process will commence.

Bugs

 * If the Brotherhood of Steel faction was chosen to assist, Elder Maxson will occasionally teleport inside the hangar where the remnants of Liberty Prime are. This can occur if one is at building at Boston Airport, making it impossible to reach him through conventional means.
 * To fix this, simply build a bed as close to the back wall, then sleep for 2 hours. If it does not work the first time, simply retry, and he should reappear.
 * If the Minutemen faction was chosen to assist, upon returning from The Institute, it will no longer be possible to assign a task to Sturges via the workshop menu, nor will he count towards the population of Sanctuary Hills. It is still possible to trade items with him, however.
 * Despite the inclusion of a sensor module on the "Items needed - Signal Interceptor" list (list is named Signal Interceptor - Items needed for both The Railroad and Brotherhood of Steel versions), one is not actually required to build any part of the teleporter.