The formation of atmospheric molecular clusters is believed to be the initial step in atmospheric aerosol New Particle Formation (NPF). Aerosol particles directly affect our global climate via aerosol-radiation interactions. This can either be scattering of sunlight by inorganic particles or absorption of radiation by black carbon. Aerosol particles also indirectly affect the global climate via aerosol-cloud interactions. For instance, aerosol particles around 50 nm or larger can act as nuclei for cloud droplet formation. Combined, these aerosol effects present the largest uncertainty in the understanding of our current climate and the prediction of climate change in the future. NPF is a large source of this uncertainty, as it remains uncertain which atmospheric vapours that are important for the initial cluster formation and the subsequent growth. Atmospheric low-volatile acids such as Sulfuric Acid (SA), Methanesulfonic Acid (MSA) and Nitric Acid (NTA) are believed to play a decisive role in the initial cluster formation and/or growth process. However, to facilitate the cluster formation process, the low-volatile acids must react with atmospheric bases such as Ammonia (AM), alkylamines (Methylamine (MA), Dimethylamine (DMA), Trimethylamine (TMA)) and diamines (Ethylenediamine (EDA), Putrescine (PUT)). At coastal regions iodine species emitted by algae are conceived to play a pivotal role in cluster formation. Depending on the saturation vapour pressure of the compounds, Highly Oxygenated organic Molecules (HOMs) can also influence cluster formation and growth. Overall, this leads to strongly bound clusters held together by a combination of hydrogen-bonded interactions and electrostatic interactions.