iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
Amorphous clusters can help crystals nucleate by concentrating dissolved molecules before an ordered crystal lattice appears. In supersaturated water containing amino acids and di- and tri-peptides, Liao, Das, Robb, Beveridge and Wynne found a continuous population of solute-rich aggregates ranging from molecular dimers and oligomers to nanometre-scale clusters and micrometre-scale particles. The larger aggregates became sites where crystals formed spontaneously and intermediates during laser-induced nucleation.
This finding answers why a crystal nucleus can emerge inside a disordered aggregate: the aggregate is not the crystal itself. It is a low-interfacial-tension, amorphous environment that forms readily, enriches the local solute concentration and lowers the kinetic difficulty of creating a tiny ordered region.
What the 2024 study found
The Chemical Science study by Zhiyu Liao, Ankita Das, Christina Glen Robb, Rebecca Beveridge and Klaas Wynne examined supersaturated aqueous solutions of amino acids and short peptides. Instead of finding one special “prenucleation” size, the authors observed a broad, continuous distribution of amorphous material.
- Molecular scale: mass spectrometry detected dimers, oligomers and clusters of at least 30 molecules, along with larger species.
- Nanometre scale: the same solute-rich population extended into nanoscale aggregates.
- Micrometre scale: dynamic light scattering (DLS) detected much larger particles that grew over time.
- Structural character: in-situ terahertz Raman spectra showed broad, unstructured low-frequency bands. Those bands differed from both the starting solution and the final crystal, indicating an amorphous phase rather than a hidden crystal.
The important result is not a single particle diameter. It is the continuity of the distribution across many orders of magnitude. A molecular oligomer, a nanometre cluster and a micrometre particle can be stages or members of the same aggregation process rather than unrelated objects.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
The authors report that larger amorphous aggregates are sites of spontaneous crystal nucleation and intermediates for laser-induced crystal nucleation. They describe this as evidence for a broad role of amorphous aggregates in the tested amino-acid and peptide systems, while stopping short of proving that every crystallizing substance follows exactly the same route.
How can amorphous clusters help crystals nucleate?
The proposed pathway has three linked steps. It differs from the simplest picture in which individual molecules collide, assemble a critical crystal-sized cluster and then grow.
- Amorphous aggregates form readily. The aggregates have a relatively low surface tension compared with a crystal–solution interface. Creating a disordered, solute-rich domain therefore requires little free-energy cost and can occur essentially without a conventional nucleation barrier.
- Solute concentration rises inside the aggregate. Molecules and oligomers are packed more densely in the aggregate than in the surrounding liquid. This local enrichment increases the frequency of productive contacts and changes the chemical environment in which ordering can occur.
- An ordered nucleus appears within the enriched domain. Once a sufficiently favorable arrangement forms inside the aggregate, a crystal nucleus can develop there. The surrounding amorphous material acts as a precursor and reservoir, not as the final crystal structure.
In this model, the difficult event is shifted. The system first creates a low-cost disordered phase, then pays the more specific structural cost of forming an ordered crystal nucleus inside it. That division can make nucleation faster or more probable than a direct, molecule-by-molecule route through a crystal-like transition state.
Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →What are prenucleation clusters?
“Prenucleation cluster” is a useful shorthand for a solute-rich aggregate that exists before a crystal nucleus is detectable. The term does not mean that every such cluster already has a crystal lattice, a fixed composition or a single characteristic size.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
In the Liao study, the evidence points to amorphous clusters across a continuum. Some are molecular oligomers; others are large particles visible to light-scattering measurements. Their common features are excess solute, disorder and a possible role before crystallization. A crystal nucleus can form within one of these domains after the domain has grown or become sufficiently enriched.
This distinction matters because a measured particle is not automatically a crystal nucleus. DLS reports an apparent hydrodynamic size, mass spectrometry reports molecular ions and oligomers, and Raman spectroscopy reports vibrational signatures. Only their combination supports the interpretation of a disordered aggregate that precedes crystal formation.
Why do crystal nuclei form inside disordered aggregates?
Lower interfacial penalty
A tiny crystal embedded directly in solution has an interface with a free-energy cost. At very small sizes, that interfacial term can outweigh the bulk free-energy gain from becoming crystalline. An amorphous aggregate presents a different interface and, according to the proposed mechanism, one with lower surface tension. It can therefore reach a useful size without crossing the same high barrier as a crystal embryo.
Recommended Free Tools
Local chemical enrichment
Supersaturation is normally calculated from the bulk solution. Inside an aggregate, however, the effective concentration of amino-acid or peptide units is higher. The local environment can move closer to the conditions required for an ordered arrangement even when the surrounding solution remains only moderately supersaturated.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Restricted molecular motion
In a dilute liquid, a molecule must encounter the right partners and orientation by chance. In an aggregate, repeated contacts and shorter intermolecular distances can make some arrangements persist long enough to reorganize. The aggregate is disordered overall, but it can contain transient ordered patches from which a stable nucleus develops.
A reservoir for subsequent growth
Once an ordered nucleus forms, nearby material is already concentrated. Molecules can be supplied from the surrounding aggregate before they must diffuse through the entire solution. This helps explain why larger aggregates, rather than the smallest oligomers, were observed as sites of spontaneous nucleation.
How the researchers identified the aggregates
No single instrument can establish size, composition and structure across this entire range. The study used complementary measurements.
| Method | What it measures | What it contributes | Important qualification |
|---|---|---|---|
| Dynamic light scattering (DLS) | Fluctuations in scattered light used to estimate apparent hydrodynamic particle sizes | Shows a broad distribution and time-dependent growth of particles in solution | Broad or polydisperse populations can make apparent sizes difficult to interpret as one physical diameter |
| Mass spectrometry | Molecular ions and oligomeric assemblies | Detects dimers, clusters through at least 30 molecules and larger molecular species | Ionisation and transfer into the instrument can affect which assemblies are observed |
| In-situ terahertz Raman spectroscopy | Low-frequency vibrational response while the sample remains under observation | Reveals broad, unstructured bands consistent with an amorphous phase distinct from solution and crystal spectra | A spectral signature identifies structural character but does not by itself supply a particle-size distribution |
Agreement among these methods is what makes the interpretation stronger: DLS supplies the mesoscale size picture, mass spectrometry links that picture to molecular oligomers, and Raman spectroscopy tests whether the material is amorphous rather than crystalline.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
How large are the clusters, and how quickly do they appear?
The reported population runs from dimers and oligomers to particles in the nanometre and micrometre ranges. Earlier DLS studies discussed by the authors reported hydrodynamic radii of approximately 75 nanometres and 500 nanometres. Those values are historical examples from prior work, not a single characteristic size measured for the 2024 study.
In the experiments summarized by Liao and colleagues, aggregates appeared on roughly a one-day timescale. The paper’s conclusions describe an overall window of about one to five days, followed by redissolution over hours under the relevant solution conditions. The timing is therefore a kinetic observation for these amino-acid and peptide solutions, not a universal clock for all crystallization systems.
Classical and nonclassical explanations compared
Classical nucleation theory remains a general framework for describing the free-energy cost of creating a critical crystal nucleus. The aggregate pathway does not discard that framework; it adds a precursor phase that changes where and how the critical ordering event occurs.
Free tools Windows power users keep installed
One-click scans. No signup required.
| Comparison axis | Direct classical picture | Aggregate-assisted, nonclassical picture |
|---|---|---|
| Precursor | Individual dissolved solute molecules assemble into a crystal-like critical cluster | Solute first gathers into a pre-existing amorphous aggregate, then orders locally |
| Free-energy landscape | A conventional crystal-nucleus barrier dominates the transition | Low-cost aggregate formation is followed by crystal nucleation in an enriched domain |
| Observable intermediate | No disordered mesoscale phase is required | Oligomers, nanometre clusters and larger amorphous particles can be measured |
| Trigger | Bulk supersaturation supplies the driving force | Bulk supersaturation combines with aggregate enrichment and may be assisted by spontaneous, laser or shear-related events |
| Scope of evidence | General theoretical framework | Directly supported here for the tested amino-acid and peptide solutions |
The phrase “nonclassical” should therefore be read carefully. It describes a pathway involving an intermediate phase, not a claim that thermodynamics no longer applies.
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
What laser-induced nucleation adds
The larger aggregates were observed not only where crystals appeared spontaneously but also as intermediates when a laser was used to induce nucleation. A laser can provide a localized perturbation that helps an already enriched aggregate cross the ordering step. The observation supports a sequence in which the aggregate exists first and the external trigger promotes crystal ordering afterward.
This does not mean that light creates every aggregate from nothing, nor that laser treatment is required for ordinary crystallization. It shows that an external stimulus can act on a pre-existing disordered intermediate. The same logic helps explain why mechanical shear or another perturbation could affect nucleation probability without directly assembling a crystal lattice molecule by molecule.
Why the result matters for crystal-growth experiments
Size distributions may be more informative than averages
If aggregates span molecular to micrometre scales, reporting only an average DLS diameter can hide the population that actually hosts nucleation. Experiments should examine distribution width, time dependence and the appearance or disappearance of large-particle tails.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
“Clear” solutions can contain important precursors
An optically transparent supersaturated solution is not necessarily molecularly uniform. Oligomers and nanoscale aggregates can be below ordinary visual resolution while still changing local concentration and nucleation kinetics.
Induction times can reflect aggregate dynamics
A delay before crystallization may represent aggregate growth, enrichment and restructuring rather than a single waiting period for a crystal embryo to appear directly in the bulk liquid. Conversely, redissolution over hours shows that the aggregate phase can be transient and reversible.
Controlling aggregates could control polymorph or location
The study does not establish a universal recipe for selecting a crystal form. It does suggest a practical research question: conditions that alter aggregate composition, lifetime, interfacial tension or local concentration may also alter where and when nucleation occurs. Any such control must be demonstrated separately for the material being studied.
Quick Recap
Limits of the evidence
- Material scope: the direct experiments concern amino acids and di- and tri-peptides in supersaturated aqueous solutions. Other substances may use different pathways.
- Interpretation of DLS: broad distributions can bias or broaden apparent hydrodynamic sizes, so DLS alone cannot prove a particular aggregate morphology.
- Cross-method coverage: the instruments observe different aspects of the population and do not track every individual particle from dimer to crystal.
- Mechanistic inference: the proposed sequence is supported by correlated observations of aggregates and nucleation, but it should not be treated as proof that every nucleus in every sample forms inside a large particle.
- Meaning of “universal”: the paper uses that term for the role suggested across the molecular-solute systems tested, not as a demonstrated law for all crystallizing matter.
A practical way to read future prenucleation-cluster claims
- Check whether the study distinguishes an amorphous aggregate from a crystal nucleus using structural data, not size alone.
- Ask whether the reported size is a single average, a distribution or a time-dependent population.
- Look for independent evidence of molecular composition, such as oligomer signals from mass spectrometry.
- Check whether spectroscopy was performed in situ and whether the aggregate spectrum differs from both solution and crystal references.
- Separate correlation from causation: aggregates associated with nucleation are strong candidates for intermediates, but the nucleation event itself must be temporally and structurally resolved.
- Keep the material and solution conditions attached to every conclusion. A mechanism established for amino acids and short peptides is a model to test elsewhere, not an automatic explanation for every crystal.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
